European Journal of Anaesthesiology最新文献

Background: Elderly patients comprise an increasing proportion of patients undergoing surgery, and they require special attention due to age-related physiological changes. Propofol is the traditional agent for anaesthesia, and recently, remimazolam, a novel ultra-short-acting benzodiazepine, has emerged as an alternative to propofol in general anaesthesia.

Objectives: We aim to compare remimazolam vs . propofol for general anaesthesia in elderly patients regarding hypotension, induction characteristics, haemodynamics and recovery outcomes.

Design: Meta-analysis with sensitivity and trial sequential analyses (TSA) to assess inconsistencies. Risk ratios and mean differences with 95% confidence intervals (95% CIs) were computed using a random effects model. Subgroups and meta-regression according to anaesthesia methods were also performed.

Data sources: We systematically searched MEDLINE, Embase and Cochrane for randomised controlled trials (RCTs) up to January 1, 2024.

Eligibility criteria: Patients at least 60 years old, comparing remimazolam vs . propofol for general anaesthesia.

Results: Eleven RCTs (947 patients) were included. Compared with propofol, remimazolam was associated with lower postinduction and intra-operative hypotension (RR 0.41, 95% CI 0.27 to 0.62, P  < 0.001) and incidence of bradycardia (risk ratio 0.58, 95% CI 0.34 to 0.98, P  = 0.04), with a higher heart rate ( P  = 0.01). The incidence of injection pain was lower ( P  < 0.001), but remimazolam was associated with a longer time to loss of consciousness ( P  < 0.001) and a higher bispectral index at loss of consciousness ( P  = 0.04). No differences were found for mean arterial pressure, emergence time, extubation time and incidence of emergence agitation. The TSA was consistent and achieved the required information size for hypotension.

Conclusions: Remimazolam significantly reduced the risk of hypotension, bradycardia and injection pain, despite an increase in the time to loss of consciousness. Remimazolam appears to be an effective and well tolerated alternative to propofol in elderly patients undergoing general anaesthesia.

Background: Drug challenge is the gold standard for identifying causative agents of drug allergies. Although clinical guidelines have recently been published, they do not recommend neuromuscular blocking agent (NMBA) drug challenges. NMBA challenges are rendered difficult by the lack of homogeneity of routine allergy work-ups and the necessity of a specialised setting. Several scenarios support NMBA challenges, such as an ambiguous allergy work-up, a high suspicion of a false-positive skin test or identification of a well tolerated alternative NMBA strategy. Furthermore, routine allergy work-ups may not recognise non-IgE mechanisms, such as IgG or MRGPRX2, whereas drug challenges may reveal them. Finally, if the culprit NMBA is not identified, subsequent anaesthesia regimens will be challenging to implement, resulting in increased risk.

Objectives: This literature review discusses the indications, strategies, doses, monitoring methods, limitations, and unresolved issues related to drug challenges for NMBAs.

Design: The literature review included randomised controlled trials, observational studies, reviews, case reports, series, and comments on humans.

Data sources: Studies were retrieved from databases (PubMed) and electronic libraries (OVID, EMBASE, Scopus, etc.).

Eligibility criteria: All studies that referred to the NMBA challenge were included without publication date limitations.

Results: NMBA challenge may be considered in NMBA anaphylaxis patients with inconclusive or ambivalent IgE diagnostic work-up under controlled conditions (presence of anaesthetists and allergists with continuous monitoring in a secured environment). To illustrate its utility, a case report of a double NMBA challenge in a patient with NMBA cross-reactivity is presented, along with biological explorations to detect subclinical cellular activation, a novel aspect of this procedure.

Conclusion: Drug challenges could be implemented during the NMBA allergy work-up under strict safety conditions at specialised centres with close collaboration between anaesthetists and allergists. This could decrease uncertainty and contribute to defining a safer strategy for subsequent anaesthetic drug regimens.

Background: As a local anaesthetic adjunct, the systemic absorption of perineural dexamethasone in the lower limb could be restricted because of decreased vascularity when compared with the upper limb.

Objectives: To compare the pharmacodynamic characteristics of intravenous and perineural dexamethasone in the lower limb.

Design: Systematic review of randomised controlled trials with meta-analysis.

Data sources: Systematic search of Central, Google Scholar, Ovid Embase and Ovid Medline to 18 July 2023.

Eligibility criteria: Randomised controlled trials, which compared the intravenous with perineural administration of dexamethasone as a local anaesthetic adjunct in peripheral nerve blocks for surgery of the lower limb.

Results: The most common peripheral nerve blocks were femoral, sciatic and ankle block. The local anaesthetic was long acting in all trials and the dose of dexamethasone was 8 mg in most trials. The primary outcome, the duration of analgesia, was investigated by all nine trials ( n  = 546 patients). Overall, compared with intravenous dexamethasone, perineural dexamethasone increased the duration of analgesia from 19.54 to 22.27 h, a mean difference [95% confidence interval (CI) of 2.73 (1.07 to 4.38) h; P  = 0.001, I2  = 87]. The quality of evidence was moderate owing to serious inconsistency. However, analysis based on the location of the peripheral nerve block, the type of local anaesthetic or the use of perineural adrenaline showed no difference in duration between intravenous and perineural dexamethasone. No differences were shown for any of the secondary outcomes related to efficacy and side effects.

Conclusion: In summary, moderate evidence supports the superiority of perineural dexamethasone over intravenous dexamethasone in prolonging the duration of analgesia. However, this difference is unlikely to be clinically relevant. Consideration of the perineural use of dexamethasone should recognise that this route of administration remains off label.

Background: Remimazolam is not only associated with a lower incidence of respiratory depression than propofol but also in itself has the risk of respiratory depression.

Objective: We investigated respiratory depression following remimazolam infusion, targeting different effect-site concentrations using target-controlled infusion.

Design: A prospective, double-blind, randomised controlled study.

Setting: Tertiary hospital, Suwon, South Korea, from April 2022 to November 2022.

Participants: One hundred and seven patients scheduled for general anaesthesia were randomised into three groups targeting remimazolam effect-site concentrations of 500 (RMZ-500) ( n  = 36), 1000 (RMZ-1000) ( n  = 35) and 1500 ng ml -1 (RMZ-1500) ( n  = 36).

Interventions: Remimazolam was solely infused for 10 min according to target effect-site concentrations. According to the degree of SpO 2 decrease, oxygen desaturations were managed with the following respiratory supports: jaw-thrust for SpO 2 less than 97%, 100% oxygen delivery for SpO 2 less than 93% and assisted ventilation for SpO 2 less than 90%.

Main outcome measures: The incidence of each respiratory support, along with respiratory variables (at baseline, 5 min and 10 min after remimazolam infusion) and loss of consciousness were observed for 10 min after remimazolam target-controlled infusion.

Results: Both RMZ-1000 and RMZ-1500 required more frequent respiratory support than RMZ-500 (both P  < 0.001), with nearly identical frequencies between RMZ-1000 and RMZ-1500. In terms of respiratory support, the incidence of assisted ventilation was significantly lower in RMZ-500 (2.8%) than RMZ-1000 (48.6%) and RMZ-1500 (50%) ( P  < 0.001). RMZ-1000 and RMZ-1500 achieved loss of consciousness in all patients; RMZ-500 only achieved loss of consciousness in 86.1% of patients ( P  = 0.010). In patients who maintained spontaneous respiration, tidal volume decreased by 41 to 48% and respiratory rate increased by 118 to 158% at 5 and 10 min, significantly compared to baseline in all groups ( P  < 0.001).

Conclusions: Remimazolam infusion, like that of other benzodiazepines, led to respiratory depression, which was more prominent at higher target effect-site concentrations. Therefore, appropriate countermeasures should be developed to prevent oxygen desaturation.

Trial registration: CRIS ( https://cris.nih.go.kr ), identifier: KCT0006952.

Background: For nearly 20 years, in international guidelines, mild therapeutic hypothermia (MTH) was an important component of postresuscitation care. However, recent randomised controlled trials have questioned its benefits. At present, international guidelines only recommend actively preventing fever, but there are ongoing discussions about whether the majority of cardiac arrest patients could benefit from MTH treatment.

Objective: The aim of this study was to compare the outcome of adult patients treated with and without MTH after cardiac arrest.

Design: Observational cohort study.

Setting: German Resuscitation Registry covering more than 31 million inhabitants of Germany and Austria.

Patients: All adult patients between 2006 and 2022 with out-of-hospital or in-hospital cardiac arrest and comatose on admission.

Main outcome measures: Primary endpoint: hospital discharge with good neurological outcome [cerebral performance categories (CPC) 1 or 2]. Secondary endpoint: hospital discharge. We used a multivariate binary logistic regression analysis to identify the effects on outcome of all known influencing variables.

Results: We analysed 33 933 patients (10 034 treated with MTH, 23 899 without MTH). The multivariate regression model revealed that MTH was an independent predictor of CPC 1/2 survival and of hospital discharge with odds ratio (95% confidence intervals) of 1.60 (1.49 to 1.72), P < 0.001 and 1.89 (1.76 to 2.02), P < 0.001, respectively.

Conclusion: Our data indicate the existence of a positive association between MTH and a favourable neurological outcome after cardiac arrest. It therefore seems premature to refrain from giving MTH treatment for the entire spectrum of patients after cardiac arrest. Further prospective studies are needed.

Background: Positive end-expiratory pressure (PEEP) is important to increase lung volume and counteract airway closure during anaesthesia, especially in obese patients. However, maintaining PEEP during emergence preoxygenation might increase postoperative atelectasis by allowing susceptible lung areas to be filled with highly absorbable oxygen that gets entrapped when small airways collapse due to the sudden loss of PEEP at extubation.

Objective: This study aimed to test the hypothesis that withdrawing PEEP just before emergence preoxygenation would better maintain postoperative oxygenation.

Design: Prospective, randomised controlled trial.

Setting: Single centre secondary hospital in Sweden between December 2019 and January 2023.

Patients: A total of 60 patients, with body mass index between 35 and 50 kg m -2 , undergoing laparoscopic bariatric surgery.

Intervention: Intraoperative ventilation was the same for all patients with a fixed PEEP of 12 or 14 cmH 2 O depending on body mass index. No recruitment manoeuvres were used. After surgery, patients were allocated to maintained PEEP or zero PEEP during emergence preoxygenation.

Main outcome measures: The primary outcome was change in oxygenation from before awakening to 45 min postoperatively as measured by estimated venous admixture calculated from arterial blood gases.

Results: Both groups had impaired oxygenation postoperatively; in the group with PEEP maintained during awakening, estimated venous admixture increased by mean 9.1%, and for the group with zero PEEP during awakening, estimated venous admixture increased by mean 10.6%, difference -1.5% (95% confidence interval -4.6 to 1.7%), P  = 0.354. Throughout anaesthesia, both groups exhibited low driving pressures and superior oxygenation compared with the awake state.

Conclusions: Withdrawing PEEP before emergence preoxygenation, did not alter early postoperative oxygenation in obese patients undergoing laparoscopic bariatric surgery. Intraoperative oxygenation was excellent despite using fixed PEEP and no recruitment manoeuvres, but deteriorated after extubation, indicating a need for future studies aimed at improving the emergence procedure.

Clinical trial number and registry: www.clinicaltrials.gov , NCT04150276. Registration date: 4 November 2019. Principal investigator: Erland Östberg.

Background: Preoperative anaemia is associated with poor postoperative outcomes; however, few studies have reported its prevalence in developing countries and its association with significant postoperative outcomes.

Objective: We aimed to identify the prevalence of anaemia and its association with postoperative outcomes in a major public hospital in Brazil.

Design: Retrospective cohort study.

Setting: Single-centre, 860-bed, quaternary university-affiliated teaching hospital in Southern Brazil.

Patients: We included adult patients who had undergone surgery between 2015 and 2019. Main outcome measures: The main outcome was the in-hospital 30-day postoperative mortality. According to the World Health Organisation, we defined anaemia and its sub-classification (mild, moderate, and severe). We developed Poisson regression models to examine the association between preoperative anaemia and outcomes.

Results: We included 15 166 patients, of whom 6387 (42.1%) were anaemic. After adjustment for confounding factors, patients with anaemia had an increased risk of in-hospital 30-day postoperative mortality (relative risk (RR) 1.69, 95% confidence interval (CI) 1.44 to 1.99, P < 0.001). Mild [relative risk (RR) 1.38, 95% CI 1.12 to 1.71, P = 0.003], moderate (RR 1.73, 95% CI 1.43 to 2.10, P < 0.001), and severe anaemia (RR 2.43, 95% CI 1.92 to 3.07, P < 0.001) were associated with the primary outcome. Anaemia increased the transfusion risk (RR 4.44, 95% CI 3.90 to 5.06, P < 0.001) and postoperative intensive care unit (ICU) admission (RR 1.09, 95% CI 1.04 to 1.16, P = 0.001).

Conclusions: Four out of 10 patients had anaemia. These patients had an increased risk of adverse postoperative outcomes. Comprehension of the magnitude and impact of anaemia is essential to establish interventions in low-resource scenarios to optimise the patient's journey.

Study registration: Institutional Review Board Registration number 40522820000005327 (Brazilian CEP/CONEP System, available in https://plataformabrasil.saude.gov.br/).