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Study Type: Scoping review (PRISMA-ScR compliant)

Key Question: What are the characteristics and impacts of live, certified music therapist-delivered therapy across the perioperative period?

Key Findings:

• 25 studies (1,821 patients, age 9 months–94 years, diverse surgical specialties) met inclusion criteria from 2,095 identified articles
• Music therapy was delivered preoperatively (n=17), intraoperatively (n=8), and postoperatively (n=15), with measurable effects on anxiety, mood, and pain across age groups
• Paediatric interventions favoured active/play-based preoperative approaches (measured behaviourally via m-YPAS); adult interventions were more evenly distributed across timepoints using self-report outcomes (VAS)

Clinical Relevance: For UK anaesthetic teams seeking non-pharmacological adjuncts to reduce perioperative anxiety and analgesic requirements, this review maps current evidence, though service availability of certified music therapists within NHS settings is likely limited.

Limitations: Small sample sizes, expectancy bias, inconsistent intervention reporting, and absence of therapist-contact control groups significantly limit generalisability.

Study Type: Retrospective entropy-balanced cohort study

Key Question: Is pulmonary artery catheter (PAC) use in adult cardiac surgery associated with improved clinical outcomes, including mortality?

Key Findings:

• PAC use was not associated with 90-day mortality (RR 0.97; 95% CI 0.72–1.30) or in-hospital mortality (RR 0.92; 95% CI 0.63–1.34)
• PAC use was associated with increased ICU length of stay (+13.1 hours), AKI (RR 1.12), prolonged inotrope use (RR 4.13), and longer mechanical ventilation (+11.3 hours)
• Higher fluid balance (+566 mL), greater RBC transfusion (+226 mL), and more vasopressor use were also observed in the PAC group

Clinical Relevance: PAC use remains common in UK cardiac theatres and ICUs; this large dataset suggests no mortality benefit and signals potential harms worth weighing against perceived haemodynamic monitoring advantages.

Limitations: Single US tertiary centre limits generalisability, and residual confounding by indication cannot be excluded despite entropy balancing.

Study Type: Prospective observational validation study (with animal model component)

Key Question: Can a novel algorithm using MAP and near-infrared spectroscopy (NIRS) cerebral oxygen saturation generate a real-time cerebral autoregulation index (CAI) that accurately identifies autoregulatory impairment?

Key Findings:

• In 71 surgical patients, the CAI achieved AUC 0.92 (95% CI 0.89–0.94), sensitivity 0.82, specificity 0.94 at a threshold of 45
• In a piglet hypotension model (n=10), performance was near-perfect: AUC 0.99, sensitivity 0.95, specificity 0.96
• Ground truth was derived retrospectively from CBF/CBFV vs MAP curves, with individual LLA and ULA identified per subject

Clinical Relevance: This algorithm could enable individualised intraoperative blood pressure targets using widely available NIRS monitoring, relevant to perioperative neuroprotection in high-risk surgical patients managed within NHS anaesthetic practice.

Limitations: Ground truth autoregulation status was determined retrospectively, and the surgical patient cohort size is modest, limiting generalisability across diverse perioperative populations.

Study Type: Retrospective chart review (single-centre)

Key Question: What is the incidence of difficult intubation and serious anaesthetic adverse events in paediatric patients with spinal muscular atrophy (SMA)?

Key Findings:

• Difficult intubation occurred in 9.4% of cases requiring endotracheal intubation (22/234), with no significant association with SMA type, age, or halo headframe use
• Severe anaesthetic adverse events were rare (0.33%; 6/1804 procedures)
• 78.9% of all procedures were lumbar punctures for nusinersen, of which 88.1% were managed with a natural airway or pre-existing tracheostomy

Clinical Relevance: As nusinersen and other disease-modifying therapies increase SMA survival, UK anaesthetists will encounter this population more frequently; a ~1-in-10 difficult intubation rate warrants routine advanced airway planning.

Limitations: Single quaternary paediatric centre limits generalisability, and retrospective design risks incomplete data capture.

Study Type: Controlled experimental study in healthy volunteers (crossover design with contralateral limb control)

Key Question: Does resolution of a single-injection axillary brachial plexus block produce objective peripheral or central hypersensitivity — a potential mechanism for rebound pain?

Key Findings:

• At 60 minutes post-motor-resolution, heat pain threshold (primary outcome) did not differ significantly between blocked and control arms (42.8°C vs 41.1°C; p=0.157)
• No consistent hypersensitivity was detected across secondary QST modalities; where differences existed, the *control* arm was paradoxically more sensitive
• Maximally sensitised values over the full post-block period also showed no pattern of post-block hyperalgesia

Clinical Relevance: These findings suggest rebound pain after peripheral nerve block is unlikely to reflect a de novo neuroplastic hyperalgesic state, supporting the hypothesis that it represents unmasked surgical pain — relevant to perioperative analgesic planning across UK surgical practice.

Limitations: Healthy volunteers without surgical pain limits direct extrapolation to clinical populations where tissue injury and inflammation may drive different nociceptive responses.

Study Type: Prospective multicentre cohort study

Key Question: Do CT-derived body composition metrics improve prediction of postoperative cardiovascular events beyond standard risk calculators in high-risk noncardiac surgical patients?

Key Findings:

• 13.2% of 1,594 patients experienced a composite cardiovascular event within 30 days postoperatively
• Three CT metrics (skeletal muscle area, muscle radiodensity, subcutaneous fat radiodensity) significantly improved discrimination over the RCRI (ΔAUC +0.136; 95% CI 0.083–0.188) and a refitted clinical model (ΔAUC +0.035; 95% CI 0.008–0.062)
• Higher adipose radiodensity and lower muscle radiodensity independently indicated greater cardiovascular risk

Clinical Relevance: The RCRI remains the dominant preoperative cardiovascular risk tool in UK anaesthetic practice; this study suggests CT body composition analysis — increasingly available given routine preoperative imaging in many surgical pathways — could meaningfully refine risk stratification.

Limitations: CT-based analysis requires dedicated software and radiological input, limiting immediate routine clinical implementation.

Study Type: Commentary/consensus report with qualitative thematic analysis

Key Question: What is the current state of medical education research in anaesthesiology, and how can it be developed into a robust, self-sustaining discipline?

Key Findings:

• No comprehensive strategy currently exists for developing education research as a discipline within anaesthesiology, with a critically limited pool of qualified research mentors
• Funding and publication output were identified as inadequate markers of current impact
• Five priority domains were identified: workforce diversification, teaching environments, GME accountability, cultural competency, and advocacy

Clinical Relevance: For UK anaesthetic training programmes, this highlights a transferable gap — the absence of structured research infrastructure in medical education risks compromising future trainee development, relevant to FICM/RCoA curriculum development and workforce planning.

Limitations: As a consensus/qualitative report from a US-based working group, findings may not directly translate to UK training structures or funding mechanisms.

Study Type: Long-term follow-up of an RCT (post hoc analysis)

Key Question: Does a restrictive perioperative IV fluid regimen in major abdominal surgery increase long-term risk of chronic kidney disease compared with a liberal regimen?

Key Findings:

• No significant difference in incident or progressive CKD (stage ≥3) between restrictive (56%) and liberal (53.4%) fluid groups (adjusted OR 1.13, 95% CI 0.91–1.41)
• No difference in eGFR secondary outcomes between groups
• Follow-up data available for only 56% of the original RELIEF cohort (1670/2983)

Clinical Relevance: Despite the original RELIEF trial showing restrictive fluid therapy increases perioperative AKI risk, this follow-up provides reassurance that this does not translate into greater long-term CKD burden — relevant when counselling patients and setting fluid strategies in UK major abdominal surgical programmes.

Limitations: Post hoc analysis with substantial attrition (only 56% followed up), introducing significant risk of selection bias and limiting confidence in the findings.