A recent Anaesthetics digest,
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Study Type: Retrospective cohort study

Key Question: Does adding fibrinogen/albumin ratio to existing risk models improve prediction of major morbidity after adult cardiac surgery with cardiopulmonary bypass?

Key Findings:

• F/A ratio alone showed poor discrimination for major morbidity (AUC 0.606, OR 1.025, 95% CI 1.061-1.091)
• EuroSCORE II demonstrated significantly better predictive performance (AUC 0.731, P<0.001)
• Adding F/A ratio to EuroSCORE II did not improve discrimination (AUC remained 0.730) or risk reclassification

Clinical Relevance: UK cardiac anaesthetists should not rely on F/A ratio for risk stratification in CPB cases, as EuroSCORE II remains the superior predictor without need for additional biomarkers.

Limitations: Retrospective single-centre design limits generalisability and may introduce selection bias.

Study Type: Retrospective cohort study

Key Question: Does severe preoperative infection increase the risk of postoperative acute kidney injury in children, and what is the combined mortality risk when both conditions occur?

Key Findings:

• Severe preoperative infection doubled the risk of postoperative AKI (aRR 2.03, 95% CI 1.51-2.74)
• Postoperative AKI alone increased 30-day mortality risk 4.6-fold (aRR 4.64, 95% CI 3.48-6.12)
• Combined preoperative infection and postoperative AKI produced a 9-fold increase in 30-day mortality (aRR 9.63, 95% CI 7.20-12.87)

Clinical Relevance: This large dataset identifies high-risk paediatric surgical patients requiring enhanced perioperative monitoring and potentially modified anaesthetic management to prevent AKI in septic children.

Limitations: Retrospective design limits causal inference and may not capture all relevant confounding variables affecting the infection-AKI-mortality pathway.

Study Type: Systematic review and meta-analysis

Key Question: What is the global prevalence of fibromyalgia in the general population and at-risk subpopulations?

Key Findings:

• Global fibromyalgia prevalence in general population: 1.40% (95% CI 0.49-2.47) across 30 million individuals from 882 studies
• Markedly higher prevalence in at-risk groups: chronic urticaria (37.1%), interstitial cystitis (30.8%), systemic sclerosis (20.6%), and inflammatory bowel disease (19.9%)
• Publication year and Human Development Index significantly moderated prevalence estimates, suggesting diagnostic inconsistency and global care disparities

Clinical Relevance: This establishes baseline fibromyalgia prevalence data crucial for UK anaesthetists managing chronic pain services and perioperative care for patients with comorbid autoimmune/inflammatory conditions where fibromyalgia rates exceed 20%.

Limitations: Substantial heterogeneity (I² = 100%) and very low certainty of evidence limit confidence in pooled estimates.

Study Type: Randomized, double-blind, controlled trial

Key Question: Does preemptive dexmedetomidine administration improve intraoperative nociceptive control and postoperative pain management in noncardiac surgery?

Key Findings:

• Dexmedetomidine significantly improved intraoperative nociception control (90.7% vs 12.5% achieving target nociception index ≤60, P<0.001)
• Moderate-to-severe postoperative pain (NRS>3) was substantially reduced at all time points: 2.8% vs 25.9% at 0 hours, 5.6% vs 29.5% at 24 hours (P=0.000)
• Secondary benefits included reduced rescue opioid consumption and lower incidence of postoperative nausea and vomiting

Clinical Relevance: This supports dexmedetomidine as an effective preemptive analgesic strategy that could enhance Enhanced Recovery After Surgery (ERAS) protocols and reduce opioid requirements in NHS perioperative care pathways.

Limitations: Single-centre study limits generalizability across different surgical populations and healthcare systems.

Study Type: Randomized controlled trial

Key Question: Does opioid-free anesthesia reduce postoperative complications compared to opioid-based anesthesia in adult cardiac surgery with cardiopulmonary bypass?

Key Findings:

• Composite complications occurred in 75.4% (OFA) vs 84.5% (control) patients (RR 0.90, 95% CI 0.80-0.99, P=0.049)
• OFA reduced cardiovascular complications (64.2% vs 75.2%) and digestive complications (2.5% vs 11.2%)
• Zero deaths in OFA group vs 6 deaths in control group (P=0.014)

Clinical Relevance: This suggests OFA protocols using ketamine, dexamethasone, lidocaine, and magnesium could reduce morbidity in UK cardiac surgery patients, potentially supporting Enhanced Recovery After Surgery pathways.

Limitations: The fragility index of 1 indicates results are statistically fragile and require validation in larger trials before changing practice.

Study Type: Commentary

Key Question: What are the health implications of plastic exposure for patients and anaesthetic providers during the perioperative period?

Key Findings:

• Perioperative plastic exposure occurs via two main routes that bypass natural defence mechanisms: intravenous (through medical devices) and inhalational (via breathing circuits and ambient particles)
• Animal studies demonstrate harm from microplastics, while human evidence shows emerging disease associations despite limited direct causation data
• Anaesthetic providers face chronic occupational exposure through masks and ambient operating theatre particles

Clinical Relevance: UK anaesthetists should be aware of potential occupational and patient safety risks from ubiquitous plastic medical devices, particularly given the NHS's commitment to environmental sustainability and staff wellbeing.

Limitations: Limited direct evidence of adverse human health effects from microplastic exposure.

Study Type: Secondary analysis of prospective, observational study

Key Question: Should patients with type 2 diabetes continue or withhold glucose-lowering drugs (metformin, SGLT2 inhibitors, GLP-1 receptor agonists) on the day of elective surgery?

Key Findings:

• Among 3,623 patients on metformin, continuing the drug on surgery day was associated with 0.47 additional days alive at home within 30 days (95% CI: 0.01-0.93, P=0.044)
• Median days alive at home at 30 days: 28 days (continued metformin) vs 27 days (discontinued metformin)
• No significant associations found for SGLT2 inhibitors (836 patients) or GLP-1 receptor agonists (304 patients), likely due to small sample sizes

Clinical Relevance: This large European study suggests continuing metformin perioperatively may provide modest benefits for diabetic patients undergoing elective surgery, challenging traditional practice of routine discontinuation.

Limitations: The clinical significance of a 0.47-day difference in days alive at home is questionable, and sample sizes were insufficient to draw conclusions about newer diabetes medications.

Study Type: Narrative review and expert opinion

Key Question: How can Patient Blood Management (PBM) principles be implemented to improve outcomes in postpartum haemorrhage management?

Key Findings:

• PBM implementation in obstetrics is associated with improved patient outcomes in postpartum haemorrhage
• Authors developed a practical algorithm for managing anaemia in pregnancy and a quick reference chart for PBM strategies during postpartum haemorrhage
• Key PBM principles include optimising, managing and preserving the patient's own blood rather than relying on transfusion

Clinical Relevance: This provides UK anaesthetists with practical tools for implementing evidence-based blood conservation strategies in obstetric emergencies, potentially reducing transfusion requirements and improving maternal outcomes in line with NHS blood conservation initiatives.

Limitations: As a narrative review and expert opinion piece, it lacks systematic methodology and may reflect author bias rather than comprehensive evidence synthesis.