British journal of anaesthesia最新文献

Background: Shared decision making is rarely used in anaesthesia consultations. Because either spinal or general anaesthesia can be appropriate for many patients undergoing surgery to repair a hip fracture, this is an appropriate context to implement and test shared decision making and associated resources for anaesthesia decisions. Conversation aids can facilitate shared decision making between clinicians, patients, and caregivers about treatment choices.

Methods: We conducted semi-structured qualitative interviews at seven sites from April to September 2024 to prepare for implementation of a conversation aid about anaesthesia choices for hip fracture surgery. Interviews elicited feedback on shared decision making and a proposed conversation aid comparing spinal and general anaesthesia.

Results: We interviewed 12 clinicians and 12 patients and caregivers. The analysis identified four themes, which we mapped to the Practical, Robust Implementation and Sustainability Model. We found (1) broad support for shared decision making in anaesthesia choices before hip fracture surgery, although it is not typically incorporated in current practice; (2) barriers to shared decision making, including institutional culture, preexisting clinician assumptions about patient preferences, and time; (3) features of a resource (i.e. the conversation aid) that can help overcome these barriers; and (4) the importance of engaging in shared decision making with an appropriate clinician. Suggestions from interviews were incorporated into the conversation aid.

Conclusions: Reasonable shared decision-making strategies such as conversation aids were seen by most participants as helpful to support shared decision making about anaesthesia options for hip fracture surgery. Engaging end users at the local level can address key implementation barriers.

Background: Ketamine, in doses suitable to induce anaesthesia in humans, gives rise to a unique state of unresponsiveness accompanied by vivid experiences and sensations, making it possible to disentangle the correlated but distinct concepts of conscious awareness and behavioural responsiveness. This distinction is often overlooked in the study of consciousness.

Methods: The mathematical framework of connectome harmonic decomposition (CHD) was used to view functional magnetic resonance imaging (fMRI) signals during ketamine-induced unresponsiveness as distributed patterns across spatial scales. The connectome harmonic signature of this particular state was mapped onto signatures of other states of consciousness for comparison.

Results: An increased prevalence of fine-grained connectome harmonics was found in fMRI signals obtained during ketamine-induced unresponsiveness, indicating higher granularity. After statistical assessment, the ketamine sedation harmonic signature showed alignment with signatures of LSD-induced (fixed effect =0.0113 [0.0099, 0.0127], P<0.001) or ketamine-induced (fixed effect =0.0087 [0.0071, 0.0103], P<0.001) psychedelic states, and misalignment with signatures seen in unconscious individuals owing to propofol sedation (fixed effect =-0.0213 [-0.0245, -0.0181], P<0.001) or brain injury (fixed effect =-0.0205 [-0.0234, -0.0178], P<0.001).

Conclusions: The CHD framework, which only requires resting-state fMRI data and can be applied retrospectively, has the ability to track alterations in conscious awareness in the absence of behavioural responsiveness on a group level. This is possible because of ketamine's unique property of decoupling these two facets, and is important for consciousness and anaesthesia research.

Background: Perioperative neurocognitive disorders (PNDs) are common complications after surgery and anaesthesia, particularly in older adults, leading to increased morbidity, mortality, and healthcare costs. Therefore, major medical societies have developed recommendations for the prevention and treatment of PNDs. Our study evaluated the reliability of large language models, specifically ChatGPT-4 and Gemini, in generating recommendations for PND management and comparing them with published guidelines.

Methods: We conducted an online cross-sectional web-based analysis over 48 h in June 2024. Artificial intelligence (AI)-generated recommendations were produced in six different locations across five countries (Switzerland, Belgium, Turkey, Canada, and the East and West Coasts of the USA). The English prompt 'a table of a bundle of care for perioperative neurocognitive disorders' was entered into ChatGPT-4 and Gemini, generating tables evaluated by independent reviewers. The primary outcomes were the Total Disagreement Score (TDS) and Quality Assessment of Medical Artificial Intelligence (QAMAI), which compared AI-generated recommendations with published guidelines.

Results: The study generated 14 tables, with TDS and QAMAI scores showing similar results for ChatGPT-4 and Gemini (2 [1-3] vs 2 [2-3], P=0.636 and 4 [4-4] vs 4 [3-4], P=0.424, respectively). AI-generated recommendations aligned well with published guidelines, with the highest alignment observed in ChatGPT-4-generated recommendations. No complete agreement with guidelines was achieved, and lack of cited sources was a noted limitation.

Conclusions: Large language models can generate perioperative neurocognitive disorder recommendations that align closely with published guidelines. However, further validation and integration of clinician feedback are required before clinical application.

Background: Remimazolam is a novel anaesthetic and sedative agent that offers several advantages, including minimal adverse haemodynamic effects and availability of a specific antidote, flumazenil. Flumazenil can induce seizures as an adverse effect; however, the incidence of seizures after flumazenil reversal after total intravenous anaesthesia with remimazolam (remimazolam-flumazenil) remains unknown. We compared the risk of seizures between total i.v. anaesthesia with remimazolam-flumazenil or propofol.

Methods: We retrospectively identified patients who underwent elective surgery (excluding brain surgery) with total i.v. anaesthesia in Japan between April 2020 and March 2022 using the Japanese Diagnosis Procedure Combination database. Patients were divided into remimazolam-flumazenil and propofol groups. Patients in the remimazolam-flumazenil group were matched to those in the propofol group at a variable ratio of 1:3 (maximum) based on age, sex, hospital, and type of surgery. We conducted conditional logistic regression analyses to assess the association between total i.v. anaesthesia with remimazolam-flumazenil and the incidence of perioperative seizures.

Results: We identified 12 033 patients who underwent total i.v. anaesthesia with remimazolam-flumazenil and 432 275 patients with propofol, creating a matched cohort of 19 105. The crude incidence of seizures was 0.66% (95% confidence interval, 0.63-0.68%). There was no significant difference in seizures between the two groups (adjusted odds ratio, 1.08; 95% confidence interval, 0.49-2.37).

Conclusions: We observed no significant differences in perioperative seizures between remimazolam-flumazenil and propofol in patients undergoing non-neurological surgery. This suggests that remimazolam-flumazenil is a possible alternative to total i.v. anaesthesia with propofol.

Background: Prehabilitation aims to enhance preoperative functional capacity through exercise, nutrition, and psychological programs. Home-based prehabilitation represents an alternative to hospital prehabilitation, with the advantage of not utilising hospital resources. This review aims to evaluate adherence and clinical effectiveness of home-based prehabilitation.

Methods: We searched PubMed, Cochrane, and Embase up to October 1, 2024 for randomised controlled trials comparing home-based prehabilitation with standard care. The primary outcome was the proportion of patients with postoperative complications. Secondary outcomes included protocol adherence, and 6-min walking test. We used risk ratios (RR) and mean differences to summarise the results. The risk of bias was assessed using RoB 2 tool.

Results: We included 29 randomised trials for a total of 3508 patients. Median adherence to home-based prehabilitation programs was 82%. Home-based prehabilitation reduced the proportion of patients with postoperative complications (508/1322 [38.4%] vs 578/1335 [43.3%], risk ratio 0.84, 95% confidence interval [CI] 0.72-0.98, P=0.02, I²=44%, low certainty). After home-based prehabilitation, 6-min walking test performance was better compared with control (MD 28.2 m (95% CI 9.5-46.9; P<0.01, I²=48). Preoperative depression (MD -0.65, 95% CI -0.87 to -0.43; P<0.001, I²=0%), postoperative anxiety (MD -0.50, 95% CI -0.75 to -0.25; P<0.001, I²=0%, low certainty) and length of hospital stays (MD -0.32 days, 95% CI -0.61 to -0.03; P=0.03, I²=45%, low certainty) were lower with home-based prehabilitation.

Conclusions: Home-based prehabilitation reduced the proportion of patients with postoperative complications, but with low certainty of evidence. It also improved preoperative functional capacity, reduced hospital stays, depression and anxiety scores, with good adherence to the intervention.

Systematic review protocol: PROSPERO (CRD42024591208).

Background: Sevoflurane and propofol are the most widely used inhaled and i.v. general anaesthetics, respectively. The mechanisms by which sevoflurane and propofol induce loss of consciousness (LOC) remain unclear. Recent studies implicate the brain dopaminergic circuit in anaesthetic-induced LOC and the cortical-striatal-thalamic-cortical loop in decoding consciousness. We investigated the contribution of the dorsal striatum, which is a critical interface between the dopaminergic circuit and the cortical-striatal-thalamic-cortical loop, in sevoflurane and propofol anaesthesia.

Methods: Electroencephalography and electromyography recordings and righting reflex tests were used to determine LOC and recovery of consciousness (ROC). The activity of D1 dopamine receptor (D1R)-expressing neurones in the dorsal striatum was monitored using fibre photometry, and regulated using optogenetic and chemogenetic methods in D1R-Cre mice.

Results: Population activities of striatal D1R neurones began to decrease before LOC and gradually returned after ROC. During sevoflurane anaesthesia, optogenetic activation of striatal D1R neurones induced ROC at cortical and behavioural levels in steady-state anaesthesia and promoted cortical activation in deep burst suppression anaesthesia. Chemogenetic inhibition of striatal D1R neurones accelerated induction (from 242.0 [46.1] to 194.0 [26.9] s; P=0.010) and delayed emergence (from 93.5 [21.2] to 133.5 [33.9] s; P=0.005), whereas chemogenetic activation of these neurones accelerated emergence (from 107 [23.7] to 81.3 [16.1] s; P=0.011). However, neither optogenetic nor chemogenetic manipulation of striatal D1R neurones had any effects on propofol anaesthesia.

Conclusions: Striatal D1R neurones modulate the state of consciousness in sevoflurane anaesthesia, but not in propofol anaesthesia.