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Summary Introduction Methods Results Discussion Remimazolam is an ultra‐short‐acting benzodiazepine sedative drug. This study aimed to compare the efficacy and safety of remimazolam with propofol for induction and maintenance of general anaesthesia in children undergoing elective surgery.Children (aged 3–6 y, ASA physical status 1 or 2, BMI 14–25 kg.m‐2) undergoing elective surgery under general anaesthesia with tracheal intubation were eligible for inclusion. Children were allocated randomly using a web‐based system to receive either remimazolam or propofol in a 3:1 ratio. After receiving fentanyl 3 μg.kg‐1, children received their allocated drug for both induction and maintenance of general anaesthesia. Induction doses were remimazolam 0.3 mg.kg‐1 or propofol 2.5 mg.kg‐1, with a second dose given should they not achieve loss of consciousness. After neuromuscular blockade and tracheal intubation, maintenance anaesthesia was achieved with an infusion either remimazolam 1–3 mg.kg‐1.h‐1 or propofol 4–12 mg.kg‐1.h‐1, alongside a remifentanil infusion (0.1–0.5 μg.kg‐1.min‐1) titrated to surgical stimulus and haemodynamic parameters. Primary outcomes were the incidence of successful induction and maintenance of anaesthesia. Secondary outcomes included: time to loss of consciousness, awakening and tracheal extubation; incidence of emergence delirium and moderate or severe pain in post‐anaesthesia care unit; incidence of negative behaviour change after surgery at postoperative day 3; and incidence of adverse events.A total of 187 children were analysed (140 allocated to remimazolam and 47 to propofol). All children achieved successful induction of anaesthesia. Successful maintenance of anaesthesia was achieved in 139 (99%) children who received remimazolam compared with 46 (98%) who received propofol (rate difference 1.4%, 95%CI ‐2.9–5.8%, p = 0.441). Adverse events occurred in 27 (19%) children who received remimazolam and 23 (49%) who received propofol.Remimazolam was well tolerated for the induction and maintenance of general anaesthesia in pre‐school‐age children and was non‐inferior to propofol. [ABSTRACT FROM AUTHOR]

A meta-analysis published in the journal Anaesthesia compared the use of remifentanil with neuromuscular blocking (NMB) drugs for tracheal intubation in adults. The study found that a remifentanil bolus provided comparable rates of successful tracheal intubation compared to NMB drugs. However, this conflicts with the findings of a recent trial that found remifentanil to be statistically inferior to NMB drugs. While the use of NMB drugs is widely recommended, the study suggests that tracheal intubation with high doses of remifentanil may be a safe alternative in certain situations. Further research is needed to investigate the efficacy of tracheal intubation without NMB drugs and to improve patient safety during the procedure. [Extracted from the article]

Summary: There is increasing interest in the use of short‐acting opioids such as remifentanil to facilitate tracheal intubation. The aim of this systematic review was to determine the efficacy and safety of remifentanil for tracheal intubation compared with neuromuscular blocking drugs in adult patients. We conducted a systematic search for randomised controlled trials evaluating remifentanil for tracheal intubation. Primary outcomes included tracheal intubation conditions and adverse events. Twenty‐one studies evaluating 1945 participants were included in the analysis. Use of remifentanil (1.5–4.0 μg.kg‐1) showed no evidence of a difference in tracheal intubation success rate compared with neuromuscular blocking drugs (risk ratio (95%CI) 0.97 (0.94–1.01); six studies; 1232 participants; I2 28%; p = 0.16; moderate‐certainty evidence). Compared with neuromuscular blocking drugs, the use of remifentanil (2.0–4.0 μg.kg‐1) makes little to no difference in terms of producing excellent tracheal intubation conditions (risk ratio (95%CI) 1.16 (0.72–1.87); two studies; 121 participants; I2 31%, p = 0.54; moderate‐certainty of evidence). There was no evidence of an effect between remifentanil (2.0–4.0 μg.kg‐1) and neuromuscular blocking drugs for bradycardia (risk ratio (95%CI) 0.44 (0.01–13.90); two studies; 997 participants; I2 81%; p = 0.64) and hypotension (risk ratio (95%CI) 1.05 (0.44–2.49); three studies; 1071 participants; I2 92%; p = 0.92). However, the evidence for these two outcomes was judged to be of very low‐certainty. We conclude that remifentanil may be used as an alternative drug for tracheal intubation in cases where neuromuscular blocking drugs are best avoided, but more studies are required to evaluate the haemodynamic adverse events of remifentanil at different doses. [ABSTRACT FROM AUTHOR]

The article discusses the need for mandatory training in the management of rare anaesthetic events, specifically focusing on patient deaths caused by unrecognised oesophageal intubation. The authors highlight that despite efforts to prevent such harm, patients continue to die from this preventable error. They argue that regular, multidisciplinary team training should be implemented to improve performance during these rare events. The authors acknowledge that there is currently no proof that this training will improve outcomes, but they believe it is necessary to prioritize patient safety. They suggest that the General Medical Council should enforce mandatory training for anaesthetists, and they reference the example of Australia and New Zealand where similar training is already in place. The authors acknowledge that implementing career-long mandatory training will come with costs, but they emphasize the importance of protecting patients and preventing future tragedies. [Extracted from the article]

This article discusses the importance of quantitative neuromuscular monitoring in anesthesia practice. It highlights the historical development of neuromuscular blocking drugs and the introduction of sugammadex, which offers the potential for antagonism of neuromuscular block. The article emphasizes the dangers of residual neuromuscular block, including prolonged recovery and postoperative complications. It also addresses the barriers to adopting quantitative monitoring, such as cost and lack of training. The authors argue that the use of quantitative monitoring is essential for optimizing neuromuscular block management and improving patient outcomes. [Extracted from the article]

Summary: Reversing neuromuscular blockade with sugammadex can eliminate residual paralysis, which has been associated with postoperative respiratory complications. There are equivocal data on whether sugammadex reduces these when compared with neostigmine. We investigated the association of the choice of reversal drug with postoperative respiratory complications and advanced healthcare utilisation. We included adult patients who underwent surgery and received general anaesthesia with sugammadex or neostigmine reversal at two academic healthcare networks between January 2016 and June 2021. The primary outcome was postoperative respiratory complications, defined as post‐extubation oxygen saturation < 90%, respiratory failure requiring non‐invasive ventilation, or tracheal re‐intubation within 7 days. Our main secondary outcome was advanced healthcare utilisation, a composite outcome including: 7‐day unplanned intensive care unit admission; 30‐day hospital readmission; or non‐home discharge. In total, 5746 (6.9%) of 83,250 included patients experienced postoperative respiratory complications. This was not associated with the reversal drug (adjusted OR (95%CI) 1.01 (0.94–1.08); p = 0.76). After excluding patients admitted from skilled nursing facilities, 8372 (10.5%) patients required advanced healthcare utilisation, which was not associated with the choice of reversal (adjusted OR (95%CI) 0.95 (0.89–1.01); p = 0.11). Equivalence testing supported an equivalent effect size of sugammadex and neostigmine on both outcomes, and neostigmine was non‐inferior to sugammadex with regard to postoperative respiratory complications or advanced healthcare utilisation. Finally, there was no association between the reversal drug and major adverse cardiovascular events (adjusted OR 1.07 (0.94–1.21); p = 0.32). Compared with neostigmine, reversal of neuromuscular blockade with sugammadex was not associated with a reduction in postoperative respiratory complications or post‐procedural advanced healthcare utilisation. [ABSTRACT FROM AUTHOR]

Residual neuromuscular blockade is associated with significant morbidity. It has been widely studied in anaesthesia; however, the incidence of residual neuromuscular blockade in patients managed in the ICU is unknown. We conducted a prospective observational study in a tertiary ICU to determine the incidence of residual neuromuscular blockade using quantitative accelerographic monitoring. We tested for residual neuromuscular blockade (defined as a train-of-four ratio < 0.9) before cessation of sedation in anticipation of tracheal extubation. We also surveyed 16 other ICUs in New Zealand to determine their use of neuromuscular monitoring. A total of 191 patients were included in the final analysis. The incidence (95%CI) of residual neuromuscular blockade was 43% (36-50%), with a similar incidence observed in non-postoperative and postoperative patients. There was a lower risk of residual neuromuscular blockade with atracurium than rocuronium (risk ratio (95%CI) of 0.39 (0.12-0.78)) and a higher risk with pancuronium than rocuronium (1.59 (1.06-2.49)). Our survey shows that, in New Zealand ICUs, monitoring of neuromuscular function is rarely carried out before tracheal extubation. When neuromuscular monitoring is undertaken, it is based on individual clinician suspicion and performed using qualitative measurements. No ICU reported using a quantitative monitor or a clinical guideline. The results demonstrate a high incidence of residual neuromuscular blockade in our ICU patients and identify the type of neuromuscular blocking drug as a possible risk factor. Monitoring neuromuscular function before tracheal extubation is not currently the standard of care in New Zealand ICUs. These data suggest that residual neuromuscular blockade may be an under-recognised problem in ICU practice. [ABSTRACT FROM AUTHOR]

In anaesthetised patients, Barker et al. used a fibreoptic laryngoscope and found the angle formed by the vocal cords decreased after induction of anaesthesia with both thiopentone and propofol before neuromuscular blockade [20]. Furthermore, patients with a predicted difficult airway were excluded, and hence, the findings are not generalisable beyond the study population, although there is no reason to believe that the vocal cords would react differently to neuromuscular blockade in these patients. Keywords: airway management; difficult airway; facemask ventilation; neuromuscular blockade; vocal cords EN airway management difficult airway facemask ventilation neuromuscular blockade vocal cords 949 952 4 08/04/22 20220901 NES 220901 Facemask ventilation is the cornerstone of airway management, and establishing its adequacy represents a critical decision branch-point in difficult airway algorithms. [Extracted from the article]

Summary: Numerous studies support the idea that neuromuscular blockade facilitates facemask ventilation after induction of anaesthesia. Although improved airway patency or pulmonary compliance and a resolution of laryngospasm have been suggested as possible causes, the exact mechanism remains unclear. We aimed to assess whether neuromuscular blockade improves facemask ventilation and to clarify whether this phenomenon is associated with the vocal cord angle. This prospective observational study included patients aged between 20 and 65 years scheduled for elective surgery under general anaesthesia. After induction of anaesthesia, patients' lungs were ventilated with pressure‐controlled ventilation using a facemask. During facemask ventilation, a flexible bronchoscope was inserted through a self‐sealing diaphragm at the elbow connector attached to the facemask and breathing circuit and positioned to allow a continuous view of the vocal cords. The mean tidal volume and vocal cord angle were measured before and after administration of neuromuscular blocking drugs. Of 108 patients, 100 completed the study. Mean (SD) tidal volume ((11.0 (3.9) ml.kg‐1 vs. 13.6 (2.6) ml.kg‐1; p < 0.001) and mean (SD) vocal cord angle (17° (10°) vs. 26° (5°); p < 0.001) increased significantly after neuromuscular blockade. The proportional increase in mean tidal volume after neuromuscular blockade was positively correlated with vocal cord angle (Spearman's ρ = 0.803; p < 0.001). In conclusion, neuromuscular blockade facilitated facemask ventilation, and the improvement was correlated with further opening of the vocal cords. [ABSTRACT FROM AUTHOR]

Summary: Numerous studies support the idea that neuromuscular blockade facilitates facemask ventilation after induction of anaesthesia. Although improved airway patency or pulmonary compliance and a resolution of laryngospasm have been suggested as possible causes, the exact mechanism remains unclear. We aimed to assess whether neuromuscular blockade improves facemask ventilation and to clarify whether this phenomenon is associated with the vocal cord angle. This prospective observational study included patients aged between 20 and 65 years scheduled for elective surgery under general anaesthesia. After induction of anaesthesia, patients' lungs were ventilated with pressure‐controlled ventilation using a facemask. During facemask ventilation, a flexible bronchoscope was inserted through a self‐sealing diaphragm at the elbow connector attached to the facemask and breathing circuit and positioned to allow a continuous view of the vocal cords. The mean tidal volume and vocal cord angle were measured before and after administration of neuromuscular blocking drugs. Of 108 patients, 100 completed the study. Mean (SD) tidal volume ((11.0 (3.9) ml.kg‐1 vs. 13.6 (2.6) ml.kg‐1; p < 0.001) and mean (SD) vocal cord angle (17° (10°) vs. 26° (5°); p < 0.001) increased significantly after neuromuscular blockade. The proportional increase in mean tidal volume after neuromuscular blockade was positively correlated with vocal cord angle (Spearman's ρ = 0.803; p < 0.001). In conclusion, neuromuscular blockade facilitated facemask ventilation, and the improvement was correlated with further opening of the vocal cords. [ABSTRACT FROM AUTHOR]

Summary: This guideline updates and replaces the 5th edition of the Standards of Monitoring published in 2015. The aim of this document is to provide guidance on the minimum standards for monitoring of any patient undergoing anaesthesia or sedation under the care of an anaesthetist. The recommendations are primarily aimed at anaesthetists practising in the UK and Ireland, but it is recognised that these guidelines may also be of use in other areas of the world. Minimum standards for monitoring patients during anaesthesia and in the recovery phase are included. There is also guidance on monitoring patients undergoing sedation and during transfer. There are new sections specifically discussing capnography, sedation and regional anaesthesia. In addition, the indications for processed electroencephalogram and neuromuscular monitoring have been updated. [ABSTRACT FROM AUTHOR]

Keywords: intensive care unit; neuromuscular blocking drugs; neuromuscular function EN intensive care unit neuromuscular blocking drugs neuromuscular function 953 955 3 08/04/22 20220901 NES 220901 Whenever and wherever neuromuscular blocking (NMB) drugs are used, they should be administered and monitored safely. When NMB drugs are given to patients whose lungs are mechanically ventilated, it is particularly important to monitor their effects, because there are many conditions that co-exist in patients with critical illness that may affect the action of NMB drugs. While the use of NMB drugs is less prevalent in the intensive care unit (ICU), a large observational study found that >12% of patients whose lungs were mechanically ventilated received NMB drugs for at least one day [2]. The use of NMB drugs has also been questioned in acute respiratory distress syndrome (ARDS); while paralysis improves the mechanics of ventilation in patients, because this is accompanied by some form of sedation, this can lead to impaired recovery. [Extracted from the article]

Summary: Transnasal humidified rapid insufflation ventilatory exchange prolongs safe apnoeic oxygenation time in children. In adults, transnasal humidified rapid insufflation ventilatory exchange is reported to have a ventilatory effect with PaCO2 levels increasing less rapidly than without it. This ventilatory effect has yet to be reproduced in children. In this non‐inferiority study, we tested the hypothesis that children weighing 10–15 kg exhibit no difference in carbon dioxide clearance when comparing two different high‐flow nasal therapy flow rates during a 10‐min apnoea period. Following standardised induction of anaesthesia including neuromuscular blockade, patients were randomly allocated to high‐flow nasal therapy of 100% oxygen at 2 or 4 l.kg−1.min−1. Airway patency was ensured by continuous jaw thrust. The study intervention was terminated for safety reasons when SpO2 values dropped < 95%, or transcutaneous carbon dioxide levels rose > 9.3 kPa, or near‐infrared spectroscopy values dropped > 20% from their baseline values, or after an apnoeic period of 10 min. Fifteen patients were included in each group. In the 2 l.kg−1.min−1 group, mean (SD) transcutaneous carbon dioxide increase was 0.46 (0.11) kPa.min−1, while in the 4 l.kg−1.min−1 group it was 0.46 (0.12) kPa.min−1. The upper limit of a one‐sided 95%CI for the difference between groups was 0.07 kPa.min−1, lower than the predefined non‐inferiority margin of 0.147 kPa.min−1 (p = 0.001). The lower flow rate of 2 l.kg−1.min−1 was non‐inferior to 4 l.kg−1.min−1 relative to the transcutaneous carbon dioxide increase. In conclusion, an additional ventilatory effect of either 2 or 4 l.kg−1.min−1 high‐flow nasal therapy in apnoeic children weighing 10–15 kg appears to be absent. [ABSTRACT FROM AUTHOR]

Summary: Transnasal humidified rapid insufflation ventilatory exchange prolongs safe apnoeic oxygenation time in children. In adults, transnasal humidified rapid insufflation ventilatory exchange is reported to have a ventilatory effect with PaCO2 levels increasing less rapidly than without it. This ventilatory effect has yet to be reproduced in children. In this non‐inferiority study, we tested the hypothesis that children weighing 10–15 kg exhibit no difference in carbon dioxide clearance when comparing two different high‐flow nasal therapy flow rates during a 10‐min apnoea period. Following standardised induction of anaesthesia including neuromuscular blockade, patients were randomly allocated to high‐flow nasal therapy of 100% oxygen at 2 or 4 l.kg−1.min−1. Airway patency was ensured by continuous jaw thrust. The study intervention was terminated for safety reasons when SpO2 values dropped < 95%, or transcutaneous carbon dioxide levels rose > 9.3 kPa, or near‐infrared spectroscopy values dropped > 20% from their baseline values, or after an apnoeic period of 10 min. Fifteen patients were included in each group. In the 2 l.kg−1.min−1 group, mean (SD) transcutaneous carbon dioxide increase was 0.46 (0.11) kPa.min−1, while in the 4 l.kg−1.min−1 group it was 0.46 (0.12) kPa.min−1. The upper limit of a one‐sided 95%CI for the difference between groups was 0.07 kPa.min−1, lower than the predefined non‐inferiority margin of 0.147 kPa.min−1 (p = 0.001). The lower flow rate of 2 l.kg−1.min−1 was non‐inferior to 4 l.kg−1.min−1 relative to the transcutaneous carbon dioxide increase. In conclusion, an additional ventilatory effect of either 2 or 4 l.kg−1.min−1 high‐flow nasal therapy in apnoeic children weighing 10–15 kg appears to be absent. [ABSTRACT FROM AUTHOR]

Summary: High‐flow nasal oxygen is increasingly used for oxygenation during apnoea. Extending apnoea duration using this technique has mainly been investigated during minor laryngeal surgery, but it is unclear how long it can be administered for before it should be discontinued due to acidosis. We aimed to describe the dynamics of arterial blood gases during apnoeic oxygenation with high‐flow nasal oxygen with jaw thrust only, to explore the limits of this technique. We included adult orthopaedic patients scheduled for general anaesthesia. After pre‐oxygenation, anaesthesia with neuromuscular blockade was induced and high‐flow nasal oxygen (70 l.min−1) was continued with jaw thrust as the only means of airway management, with monitoring of vital signs and arterial blood gas sampling every 5 minutes. Apnoeic oxygenation with high‐flow nasal oxygen was discontinued when arterial carbon dioxide tension (PaCO2) exceeded 12 kPa or pH fell to 7.15. This technique was used in 35 patients and median (IQR [range]) apnoea time was 25 (20–30 [20–45]) min and was discontinued in all patients when pH fell to 7.15. The mean (SD) PaCO2 increase was 0.25 (0.06) kPa.min−1 but it varied substantially (range 0.13–0.35 kPa.min−1). Mean (SD) arterial oxygen tension was 48.6 (11.8) kPa when high‐flow nasal oxygen was stopped. Patients with apnoea time > 25 minutes were significantly older (p = 0.025). We conclude that apnoeic oxygenation with high‐flow nasal oxygen resulted in a significant respiratory acidosis that varies substantially on the individual level, but oxygenation was maintained. [ABSTRACT FROM AUTHOR]

Summary: There are no current descriptions of general anaesthesia characteristics for obstetric surgery, despite recent changes to patient baseline characteristics and airway management guidelines. This analysis of data from the direct reporting of awareness in maternity patients' (DREAMY) study of accidental awareness during obstetric anaesthesia aimed to describe practice for obstetric general anaesthesia in England and compare with earlier surveys and best‐practice recommendations. Consenting patients who received general anaesthesia for obstetric surgery in 72 hospitals from May 2017 to August 2018 were included. Baseline characteristics, airway management, anaesthetic techniques and major complications were collected. Descriptive analysis, binary logistic regression modelling and comparisons with earlier data were conducted. Data were collected from 3117 procedures, including 2554 (81.9%) caesarean deliveries. Thiopental was the induction drug in 1649 (52.9%) patients, compared with propofol in 1419 (45.5%). Suxamethonium was the neuromuscular blocking drug for tracheal intubation in 2631 (86.1%), compared with rocuronium in 367 (11.8%). Difficult tracheal intubation was reported in 1 in 19 (95%CI 1 in 16–22) and failed intubation in 1 in 312 (95%CI 1 in 169–667). Obese patients were over‐represented compared with national baselines and associated with difficult, but not failed intubation. There was more evidence of change in practice for induction drugs (increased use of propofol) than neuromuscular blocking drugs (suxamethonium remains the most popular). There was evidence of improvement in practice, with increased monitoring and reversal of neuromuscular blockade (although this remains suboptimal). Despite a high risk of difficult intubation in this population, videolaryngoscopy was rarely used (1.9%). [ABSTRACT FROM AUTHOR]

Celebrating 75 years of Anaesthesia: our past, present and future. At the time, the balance between achieving optimal neuromuscular blockade to facilitate surgery and the need to avoid excessive depth of anaesthesia was a cause of much concern, and the use of intocostrin (curare) was postulated as a new and exciting solution. Depth of anaesthesia Mallinson reminds us of Guedel's classification of clinically assessing the depth of anaesthesia. Mallinson was correct that neuromuscular blocking drugs made surgery more practicable and effective, and arguably revolutionised the practice of anaesthesia; however, he could not have foreseen their association with two of the most feared peri-operative complications for patients and anaesthetists alike: accidental awareness during general anaesthesia; and residual neuromuscular blockade following recovery from anaesthesia. [Extracted from the article]

Summary: It is recognised that high‐flow nasal therapy can prevent desaturation during airway management. Studies in spontaneously breathing patients show an almost linear relationship between flow rate and positive airway pressure in the nasopharynx. Positive airway pressure has been suggested as one of the possible mechanisms explaining how high‐flow nasal therapy works. However, data on pressures generated by high‐flow nasal therapy in apnoeic adults under general anaesthesia are absent. This randomised controlled crossover trial investigated airway pressures generated by different flow rates during high‐flow nasal therapy in anaesthetised and paralysed apnoeic patients, comparing pressures with closed and open mouths. Following induction of anaesthesia and neuromuscular blockade, a continuous jaw thrust was used to enable airway patency. Airway pressure was measured in the right main bronchus, the middle of the trachea and the pharynx, using a fibreoptically‐placed catheter connected to a pressure transducer. Each measurement was randomised with respect to closed or open mouth and different flow rates. Twenty patients undergoing elective surgery were included (mean (SD) age 38 (18) years, BMI 25.0 (3.3) kg.m‐2, nine women, ASA physical status 1 (35%), 2 (55%), 3 (10%). While closed mouths and increasing flow rates demonstrated non‐linear increases in pressure, the pressure increase was negligible with an open mouth. Airway pressures remained below 10 cmH2O even with closed mouths and flow rates up to 80 l.min−1; they were not influenced by catheter position. This study shows an increase in airway pressures with closed mouths that depends on flow rate. The generated pressure is negligible with an open mouth. These data question positive airway pressure as an important mechanism for maintenance of oxygenation during apnoea. [ABSTRACT FROM AUTHOR]

Summary: It is recognised that high‐flow nasal therapy can prevent desaturation during airway management. Studies in spontaneously breathing patients show an almost linear relationship between flow rate and positive airway pressure in the nasopharynx. Positive airway pressure has been suggested as one of the possible mechanisms explaining how high‐flow nasal therapy works. However, data on pressures generated by high‐flow nasal therapy in apnoeic adults under general anaesthesia are absent. This randomised controlled crossover trial investigated airway pressures generated by different flow rates during high‐flow nasal therapy in anaesthetised and paralysed apnoeic patients, comparing pressures with closed and open mouths. Following induction of anaesthesia and neuromuscular blockade, a continuous jaw thrust was used to enable airway patency. Airway pressure was measured in the right main bronchus, the middle of the trachea and the pharynx, using a fibreoptically‐placed catheter connected to a pressure transducer. Each measurement was randomised with respect to closed or open mouth and different flow rates. Twenty patients undergoing elective surgery were included (mean (SD) age 38 (18) years, BMI 25.0 (3.3) kg.m‐2, nine women, ASA physical status 1 (35%), 2 (55%), 3 (10%). While closed mouths and increasing flow rates demonstrated non‐linear increases in pressure, the pressure increase was negligible with an open mouth. Airway pressures remained below 10 cmH2O even with closed mouths and flow rates up to 80 l.min−1; they were not influenced by catheter position. This study shows an increase in airway pressures with closed mouths that depends on flow rate. The generated pressure is negligible with an open mouth. These data question positive airway pressure as an important mechanism for maintenance of oxygenation during apnoea. [ABSTRACT FROM AUTHOR]

Anaphylaxis in pregnancy is a rare but severe complication for both mother and infant. Population-based data on anaphylaxis in pregnancy are lacking from mainland European countries. This multinational study presents the incidence, causative agents, management and maternal and infant outcomes of anaphylaxis in pregnancy. This descriptive multinational study used a combination of retrospective (Finnish medical registries) and prospective population-based studies (UK, France, Belgium and the Netherlands) to identify cases of anaphylaxis. Sixty-five cases were identified among 4,446,120 maternities (1.5 per 100,000 maternities; 95%CI 1.1-1.9). The incidence did not vary between countries. Approximately three-quarters of reactions occurred at the time of delivery. The most common causes were antibiotics in 27 women (43%), and anaesthetic agents in 11 women (17%; including neuromuscular blocking drugs, 7), which varied between countries. Anaphylaxis had very poor outcomes for one in seven mothers and one in seven babies; the maternal case fatality rate was 3.2% (95%CI 0.4-11.0) and the neonatal encephalopathy rate was 14.3% (95%CI 4.8-30.3). Across Europe, anaphylaxis related to pregnancy is rare despite having a multitude of causative agents and different antibiotic prophylaxis protocols. [ABSTRACT FROM AUTHOR]

Deep neuromuscular block aims to improve operative conditions during laparoscopic surgery with a lower intra-abdominal pressure. Studies are conflicting on whether meaningful improvements in quality of recovery occur beyond emergence, and whether lower intra-abdominal pressure is achieved. In this pragmatic randomised trial with 1:1 allocation, adults undergoing elective laparoscopic surgery were allocated to moderate neuromuscular block reversed with neostigmine, or deep neuromuscular block reversed with sugammadex. Allocation was revealed to the anaesthetist only. Primary outcome was cognitive recovery of the Postoperative Quality of Recovery Scale, 7 days after surgery. Secondary outcomes included recovery in other domains of the Postoperative Quality of Recovery Scale at 15 min and 40 min; days 1, 3, 7, 14; and 1 and 3 months after surgery. Chi-square test was used for the primary outcome, and generalised linear mixed model for recovery over time between groups. Of 350 participants randomised, 140 (deep) and 144 (moderate) were analysed for the primary outcome. There was no difference in the Postoperative Quality of Recovery Scale cognitive domain at day 7 (deep 92.9% vs. moderate 91.8%, OR 1.164; 95%CI 0.486-2.788, p = 0.826), or at any other time-point. No significant difference was observed for physiological, emotive, activities of daily living, nociception, or overall recovery. Length of stay in the recovery area (mean (SD) deep 108 (58) vs. moderate 109 (57) min, p = 0.78) and hospital (1.8 (1.9) vs. 2.6 (3.5) days, p = 0.019) was not different. Intra-abdominal pressure and surgical operating conditions were not different between groups. Deep neuromuscular block did not improve quality of recovery compared with moderate neuromuscular block in operative laparoscopic surgery over a 1-h duration. [ABSTRACT FROM AUTHOR]

Timely application of objective neuromuscular monitoring can avoid residual neuromuscular blockade. We assessed the frequency of objective neuromuscular monitoring with acceleromyography and the last recorded train-of-four ratio in a cohort of Danish patients. We extracted data from all patients receiving general anaesthesia from November 2014 to November 2016 at six hospitals in the Zealand Region of Denmark. Acceleromyography was available in all operating rooms and data were recorded automatically. The primary outcome measure was acceleromyography use in patients receiving neuromuscular blocking agents, divided into non-depolarising agents and succinylcholine only. The dataset included 76,743 cases, of which 30,430 received a neuromuscular blocking drug. Non-depolarising drugs were used in 16,525 (54%) and succinylcholine as the sole drug in 13,905 (46%) cases. Acceleromyography was used in 14,463 (88%) patients who received a non-depolarising neuromuscular blocking drug and in 4224 (30%) receiving succinylcholine alone. Acceleromyography use varied between the departments from 58% to 99% for non-depolarising drugs and from 3% to 79% for succinylcholine alone. The median (IQR [range]) of the last recorded train-of-four ratio before tracheal extubation was 0.97 (0.90-1.06 [0.01-2.20]) when non-depolarising drugs were used, and was less than 0.9 in 22% of cases. The OR for oxygen desaturation was higher with the use of succinylcholine [2.51 (95%CI 2.33-2.70) p < 0.001] and non-depolarising drugs [2.57 (95%CI 2.32-2.84) p < 0.001] as compared with cases where no neuromuscular blockade drug was used. In conclusion, acceleromyography was almost always used in cases where non-depolarising neuromuscular blocking drugs were used, but a train-of-four ratio of 0.9 was not always achieved. Monitoring was used in less than 30% of cases where succinylcholine was the sole drug used. [ABSTRACT FROM AUTHOR]

Sugammadex, a specific reversal agent for steroidal neuromuscular blocking drugs, has on occasion been reported to be associated with clinical signs of awakening. We performed a study to systematically search for an increase in bispectral index values and signs of awakening in patients maintained under general anaesthesia following sugammadex administration. Patients, scheduled to receive general anaesthesia with neuromuscular blockade, were included in this double-blind randomised crossover study. After surgery was completed, and while the train-of-four ratio was zero, intravenous anaesthesia was continued with the aim of maintaining the bispectral index in the range of 40-60. Patients then received either sugammadex 4 mg.kg-1 or saline. In cases of incomplete reversal of neuromuscular blockade after 5 min, patients received the other drug. Bispectral index and train-of-four monitoring were recorded every minute and clinical signs of awakening noted. Fifty-one patients completed the study. Median (IQR [range]) bispectral index values increased after sugammadex administration from 49 (43-53 [38-64]) to 63 (53-80 [45-97]) (p < 0.01) with an increase of ≥ 20 in 22 patients; 14 (27%) patients had clinical signs of awakening. Saline had no effect on bispectral index values, clinical signs of awakening or degree of neuromuscular blockade. This study confirms that reversal of neuromuscular blockade with sugammadex may be associated with clinical signs of awakening despite maintenance of anaesthesia. Intravenous anaesthesia should be maintained until complete recovery of muscle function is achieved, especially when sugammadex is administered. [ABSTRACT FROM AUTHOR]

Doxapram is now known to act in a manner akin to hypoxia at the TASK channel of the carotid body glomus cell [25]. Influence of propofol on isolated neonatal rat carotid body glomus cell response to hypoxia and hypercapnia. Differential effects of halothane and isoflurane on carotid body glomus cell intracellular Ca2 + and background K+ channel responses to hypoxia. [Extracted from the article]

The extent of neuromuscular blockade during anaesthesia is frequently measured using a train-of-four stimulus. Various monitors have been used to quantify the train-of-four, including mechanomyography, acceleromyography and electromyography. Mechanomyography is often considered to be the laboratory gold standard of measurement, but is not commercially available and has rarely been used in clinical practice. Acceleromyography is currently the most commonly used monitor in the clinical setting, whereas electromyography is not widely available. We compared a prototype electromyograph with a newly constructed mechanomyograph and a commercially available acceleromyograph monitor in 43 anesthetised patients. The mean difference (bias; 95% limits of agreement) in train-of-four ratios was 4.7 (-25.2 to 34.6) for mechanomyography vs. electromyography; 14.9 (-13.0 to 42.8) for acceleromyography vs. electromyography; and 9.8 (-31.8 to 51.3) for acceleromyography vs. mechanomyography. The mean difference (95% limits of agreement) in train-of-four ratios between opposite arms when using electromyography was -0.7 (-20.7 to 19.3). There were significantly more acceleromyography train-of-four values > 1.0 (23%) compared with electromyography or mechanomography (2-4%; p < 0.0001). Electromyography most closely resembled mechanomyographic assessment of neuromuscular blockade, whereas acceleromyography frequently produced train-of-four ratio values > 1.0, complicating the interpretation of acceleromyography results in the clinical setting. [ABSTRACT FROM AUTHOR]

Neostigmine reverses non-depolarising neuromuscular blockade, but may cause muscle weakness when administered after full recovery of neuromuscular function. We hypothesised that neostigmine in therapeutic doses impairs muscle strength and respiratory function in awake healthy volunteers. Twenty-one volunteers were randomised to receive two doses of either intravenous (i.v.) neostigmine 2.5 mg with glycopyrrolate 450 μg (neostigmine group, n = 14) or normal saline 0.9% (placebo group, n = 7). The first dose was administered immediately after obtaining baseline measurements, and the second dose was administered 15 min later. All 14 volunteers in the neostigmine group received the first dose, mean (SD) 35 (5.8) μg.kg-1 , but only nine of these volunteers agreed to receive the second dose, 34 (3.5) ?g.kg-1 . The primary outcome was hand grip strength. Secondary outcomes were train-of-four ratio, single twitch height, forced expiratory volume in 1 s, forced vital capacity, forced expiratory volume in 1 s/forced vital capacity ratio, oxygen saturation, heart rate and mean arterial pressure. The first dose of intravenous neostigmine with glycopyrrolate resulted in reduced grip strength compared with placebo, -20 (20) % vs. +4.3 (9.9) %, p = 0.0016; depolarising neuromuscular blockade with decreased single twitch height, -14 (11) % vs. -3.8 (5.6) %, p = 0.0077; a restrictive spirometry pattern with decreased predicted forced expiratory volume in 1 s, -15 (12) % vs. -0.47 (3.4) %, p = 0.0011; and predicted forced vital capacity, -20 (12) % vs. -0.59 (3.2) %, p < 0.0001 at 5 min after administration. The second dose of neostigmine with glycopyrrolate further decreased grip strength mean (SD) -41 (23) % vs. +1.0 (15) %, p = 0.0004; single twitch height -25 (15) % vs. -2.5 (6.6) %, p = 0.0030; predicted forced expiratory volume in 1 s -23 (24) % vs. -0.7 (4.4) %, p = 0.0063; and predicted forced vital capacity, -27.1 (22.0) % vs. -0.66 (3.9) %, p = 0.0010. Train-of-four ratio remained unchanged (p = 0.22). In healthy volunteers, therapeutic doses of neostigmine induced significant and dose-dependent muscle weakness, demonstrated by a decrease in maximum voluntary hand grip strength and a restrictive spirometry pattern secondary to depolarising neuromuscular blockade. [ABSTRACT FROM AUTHOR]

Some short procedures require deep neuromuscular blockade, which needs to be reversed at the end of the procedure. Forty-four patients undergoing elective laryngeal micro-surgery were randomly allocated into two groups: rocuronium 0.45 mg.kg-1 with neostigmine (50 μg.kg-1 with glycopyrrolate 10 μg.kg-1 ) reversal (moderate block group) vs. rocuronium 0.90 mg.kg-1 with sugammadex (4 mg.kg-1 ) reversal (deep block group). The primary outcome was the intubating conditions during laryngoscopy secondary outcomes included recovery of neuromuscular block; conditions for tracheal intubation; satisfaction score as determined by the surgeon; onset of neuromuscular block; and postoperative sore throat. The onset of neuromuscular block was more rapid, and intubation conditions and ease of intra-operative laryngoscopy were more favourable, and the satisfaction score was lower in the moderate block group compared with the deep block group. No difference was found in the incidence of postoperative sore throat. In laryngeal micro-surgery, the use of rocuronium 0.9 mg.kg-1 with sugammadex for reversal was associated with better surgical conditions and a shorter recovery time than rocuronium 0.45 mg.kg-1 with neostigmine. [ABSTRACT FROM AUTHOR]

Standardisation, syringe labelling and prefilled syringes. Introducing empty red-barrelled syringes into the anaesthesia workplace is a superficially attractive idea but again only serves to give the impression of meaningful action on safety and does not stand up to scrutiny of the deeper understanding of human factors. It is the equivalent of pre-labelling empty syringes and then making them available to humans who are well-known to sometimes inadvertently fill them with the wrong medicine. [Extracted from the article]

Nine patients did not achieve recovery of the second twitch of the train-of-four and 11 did not reach recovery of the third twitch, either because further rocuronium was needed to improve surgical conditions (12 patients) or because surgery ended earlier than expected (8 patients). Type-2 diabetes mellitus is highly prevalent among surgical patients, including an estimated 10% prevalence of undiagnosed diabetes [1]. We included patients with type-2 diabetes without neuropathy or nephropathy and patients without diabetes. [Extracted from the article]

The authors comment on a report about muscle weakness, fasiculations and multiple subjective symptoms induced by the administration of neostiginine plus glycopyrrolate in the absence of non-depolarizing neuromuscular blocker (NMB). They attribute the difference in patients' response to neostigmine to receptor occupancy by the non-depolarizing NMB. They discuss the role of non-depolarizing NMB at the neuromuscular junction in the efficacy of an anticholinesterase on neuromuscular transmission.

We congratulate Dr Klein et al. and the Association of Anaesthetists on the timely recommendations for standards of monitoring [1]. Likewise, for a baseline TOF ratio of 150%, a raw TOF ratio of 90% equates to 60% (90/150 × 100). [Extracted from the article]