Daily Anesthesiology Research Analysis
A multicenter randomized trial (BigpAK-2) showed that a biomarker-guided perioperative prevention bundle significantly reduced moderate-to-severe acute kidney injury after major surgery. A single-center RCT in Anesthesiology found that individualized flow-controlled ventilation cut mechanical power by 55% and signaled fewer complications despite a neutral primary biomarker endpoint. A meta-analysis in neurosurgical anesthesiology demonstrated that infection-prevention bundles nearly halved exter
Summary
A multicenter randomized trial (BigpAK-2) showed that a biomarker-guided perioperative prevention bundle significantly reduced moderate-to-severe acute kidney injury after major surgery. A single-center RCT in Anesthesiology found that individualized flow-controlled ventilation cut mechanical power by 55% and signaled fewer complications despite a neutral primary biomarker endpoint. A meta-analysis in neurosurgical anesthesiology demonstrated that infection-prevention bundles nearly halved external ventricular drain infections.
Research Themes
- Perioperative kidney protection and biomarker-guided prevention
- Lung-protective intraoperative ventilation strategies
- Infection prevention bundles in neurocritical care
Selected Articles
1. A preventive care strategy to reduce moderate or severe acute kidney injury after major surgery (BigpAK-2); a multinational, randomised clinical trial.
In high-risk major surgical patients identified by clinical factors and urinary tubular stress biomarkers, a KDIGO-aligned preventive bundle reduced moderate-to-severe AKI within 72 hours (14.4% vs 22.3%; OR 0.57; NNT ≈12) without increasing adverse events. The pragmatic strategy focused on hemodynamic optimization, nephrotoxin avoidance, and glycemic control.
Impact: This large, multinational RCT demonstrates that a biomarker-guided prevention bundle can meaningfully reduce clinically significant AKI after major surgery, a frequent and serious perioperative complication.
Clinical Implications: Perioperative teams should consider implementing biomarker-enriched risk stratification and standardized kidney-protection bundles (advanced hemodynamic monitoring, volume and pressure targets, nephrotoxin/contrast avoidance, hyperglycemia prevention) to reduce moderate-to-severe AKI.
Key Findings
- Moderate/severe AKI within 72 hours was reduced from 22.3% to 14.4% (OR 0.57; NNT ≈12).
- No increase in adverse events including atrial fibrillation, significant bleeding, or reoperation.
- Biomarker-enriched selection plus KDIGO-based supportive care bundle achieved clinically meaningful benefit.
Methodological Strengths
- Multicenter randomized design with trial registration (NCT04647396).
- Biomarker-enriched risk stratification and intention-to-treat analysis.
Limitations
- Short primary outcome window (72 hours) may not capture longer-term kidney outcomes.
- Open-label pragmatic implementation could introduce performance bias; industry funding (BioMérieux).
Future Directions: Evaluate durability of kidney protection (e.g., MAKE90), cost-effectiveness, and implementation strategies across diverse health systems; assess additive value of specific biomarker thresholds and automated clinical decision support.
BACKGROUND: Acute kidney injury (AKI) is a common and important complication of major surgery, yet recommended preventive care is rarely administered. We used urinary biomarkers to identify patients at high risk of AKI and implemented a preventive care strategy to reduce AKI within 72 h after major surgery. METHODS: BigpAK-2 was a multicentre randomised clinical trial done in 34 hospitals in Europe. Patients (aged ≥18 years) undergoing major surgery at high risk for AKI identified by predefined clinical risk factors and tubular stress biomarkers were randomly assigned to usual care or a preventive care strategy as per recommendations by the Kidney Disease Improving Global Outcome guidelines: advanced hemodynamic monitoring, optimisation of volume status and haemodynamics, avoidance of nephrotoxic drugs and radiocontrast agents, and prevention of hyperglycaemia. The primary outcome was the occurrence of moderate or severe AKI within 72 h after surgery, assessed in the intention-to-treat population. Safety was assessed by comparing rates of adverse events between groups. This trial is registered with ClinicalTrials.gov, NCT04647396. FINDINGS: From Nov 25, 2020, to June 21, 2024, 7873 patients were screened and 1180 (15·0%) were randomly assigned (589 [49·9%] to the intervention group and 591 [50·1%] to the control group). Among the 1176 patients available for the primary endpoint analysis, moderate or severe AKI occurred in 84 (14·4%) patients in the intervention group and in 131 (22·3%) patients in the control group (odds ratio 0·57 [95% CI 0·40-0·79; p=0·0002; number needed to treat 12 [7-33]). There were no differences in adverse events. The most common adverse events were atrial fibrillation (50 [8·8%] in the intervention group vs 56 (9·7%) in the control group), hemodynamically relevant arrhythmias (41 [7·2%] in the intervention group vs 50 [8·6%] in the control group), significant bleeding or haemorrhage (34 [6·0%] in the intervention group vs 31 [5·3%] in the control group), and unplanned return to the operating room (29 [5·1%] in the intervention vs 38 [6·5%] in the control group). INTERPRETATION: Among adults at high risk for AKI undergoing major surgery, a preventive care strategy consisting of supportive measures and avoidance of nephrotoxins significantly reduced the occurrence of moderate or severe AKI without increasing adverse events. FUNDING: BioMérieux.
2. Individualized Flow-Controlled versus Pressure-Controlled Ventilation in Cardiac Surgery: A Randomized Controlled Trial.
In 140 adults undergoing on-pump cardiac surgery, flow-controlled ventilation did not reduce IL-8 at 6 hours versus pressure-controlled ventilation but reduced mechanical power by 55% and signaled fewer postoperative complications and shorter hospital stay. FCV achieved normocapnia with lower respiratory rates and minute ventilation.
Impact: FCV is an emerging ventilation mode that substantially lowers mechanical power, a key driver of ventilator-induced lung injury, with encouraging signals in clinical outcomes.
Clinical Implications: Anesthesiologists may consider FCV as a lung-protective strategy in cardiac surgery, recognizing that definitive clinical benefit requires larger multicenter trials and that primary biomarker endpoints were neutral.
Key Findings
- No significant difference in IL-8 at 6 hours post-CPB between FCV and PCV.
- FCV reduced perioperative mechanical power by 55% with lower respiratory rates and minute ventilation.
- Exploratory secondary outcomes favored FCV: fewer pulmonary/extrapulmonary complications and shorter hospital stay.
Methodological Strengths
- Prospective randomized controlled design with protocolized ventilation targets.
- Clinically relevant endpoints including mechanical power and postoperative complications.
Limitations
- Single-center design; primary endpoint neutral, with secondary outcomes exploratory.
- Higher driving pressures and tidal volumes in FCV may confound mechanistic interpretation.
Future Directions: Conduct multicenter, adequately powered RCTs with hard clinical endpoints (e.g., pneumonia, hypoxemia, ventilator days) and standardized FCV protocols; evaluate long-term pulmonary outcomes and cost-effectiveness.
BACKGROUND: Patients undergoing on-pump cardiac surgery are at high risk for perioperative lung injury and a hyper-inflammatory state associated with postoperative complications. We investigated the hypothesis that Flow-Controlled Ventilation (FCV) reduces the inflammatory stimulus compared to conventional Pressure-Controlled Ventilation (PCV) in this patient cohort. FCV has the unique feature of controlling airway flows during inspiration and expiration and the potential to reduce mechanical power of invasive ventilation. METHODS: In this single-center randomized controlled trial, 140 adult patients undergoing cardiac surgery with cardiopulmonary bypass were allocated 1:1 to FCV or PCV from Aug 10, 2020, to Nov 16, 2022. Participants received perioperatively either individualized FCV with a compliance-guided positive end-expiratory pressure (PEEP) and a compliance-guided driving pressure (ΔP) or PCV with a compliance-guided PEEP and ΔP for tidal volumes of 6-8 ml/kg predicted body weight. Postoperative plasmatic interleukin 8 (IL-8) levels six hours after cardiopulmonary bypass were defined as the primary endpoint. Explorative secondary outcomes included incidences of postoperative pulmonary and extrapulmonary complications, and hospital length of stay. RESULTS: Median postoperative IL-8 levels did not differ significantly between FCV and PCV (FCV 3.08 vs. PCV 3.60, beta coefficient 0.08 pg/ml, 95% CI -0.17 to 0.33; P = 0.573). ΔP values and tidal volumes were higher in the FCV group, but FCV yielded lower respiratory rates and minute volumes required for normocapnia. As a result, the FCV approach reduced the perioperatively applied mechanical power by 55%. After FCV, incidences of single postoperative pulmonary complications (e.g. confirmed pneumonia, moderate and severe hypoxemia) and any postoperative extrapulmonary complication were lower, and the hospital stay shorter. CONCLUSIONS: FCV did not reduce plasmatic IL-8 levels at the predefined timepoint six hours after cardiopulmonary bypass. However, the reduction of mechanical power during individualized FCV application and the findings of the explorative secondary study outcomes justify future trials.
3. Effect of Bundled Care on External VentricularDrain Infections: A Systematic Review and Meta-analysis.
Across 22 studies including 6,330 patients, infection-prevention bundles for external ventricular drains halved infection risk (pooled RR 0.46, 95% CI 0.33–0.65). Core elements were hand hygiene and preinsertion antibiotics, with added benefits suggested for antimicrobial-impregnated catheters, tunneled placement, and structured education.
Impact: This synthesis provides quantitative evidence supporting bundled EVD infection-prevention practices and highlights components associated with achieving low infection rates.
Clinical Implications: Neurocritical care teams should standardize EVD bundles emphasizing hand hygiene and preinsertion antibiotics, and consider antimicrobial-impregnated/tunneled catheters and staff education to achieve infection rates below 5%.
Key Findings
- Bundle implementation reduced EVD infection risk (pooled RR 0.46; 95% CI 0.33–0.65) with moderate heterogeneity (I²=50.9%).
- Hand hygiene (100%) and preinsertion antibiotics (91%) were most commonly implemented elements.
- In studies with <5% infection, antimicrobial-impregnated catheters, tunneled placement, and structured education were more frequently used.
Methodological Strengths
- Registered protocol (PROSPERO) with comprehensive database search and dual independent review.
- Random-effects meta-analysis with Hartung-Knapp adjustment and heterogeneity assessment.
Limitations
- Predominantly observational studies with variability in bundle components and definitions.
- Moderate heterogeneity; potential publication bias not fully excluded.
Future Directions: Prospective multicenter studies/RCTs testing standardized EVD bundles and specific components; evaluate sustainability, cost-effectiveness, and microbiological outcomes.
External ventricular drains (EVDs) are critical for managing acute intracranial conditions but are associated with infections. We conducted a systematic review and meta-analysis to evaluate whether the implementation of infection prevention bundles reduces the risk of EVD-associated infections, which was registered with PROSPERO on July 25, 2024 (https://www.crd.york.ac.uk/prospero/): CRD42024573168. PubMed, EMBASE, and Scopus databases were systematically searched for studies reporting EVD infection rates with and without bundle implementation. Two reviewers independently assessed bundle element presence and extracted infection outcomes. The meta-analysis was performed using a random-effects model with Hartung-Knapp adjustment, and heterogeneity was assessed using the I² statistic. An exploratory subgroup analysis compared bundle element implementation between studies achieving <5% infection rates and those with ≥5%. Twenty-two studies were analyzed, including 6330 patients (3895 in the bundle group and 2435 in the nonbundle group). Hand hygiene (100%) and administration of preinsertion antibiotics (91%) were the most frequently implemented bundle elements, whereas structured weaning protocols were infrequently reported (9%). Bundle implementation was associated with a significant reduction in EVD infection risk (pooled Risk Ratio [RR]: 0.46, 95% CI: 0.33-0.65, P<0.001). Moderate heterogeneity was observed across studies (I²=50.9%). The use of antimicrobial-impregnated catheters, tunneled catheter placement, and structured education programs were more frequently present among studies achieving infection rates <5%. Implementing an infection prevention bundle is associated with a significant reduction in EVD infections. Adoption of core practices, supplemented by technology enhancements and education programs, may further optimize infection prevention strategies.