Daily Anesthesiology Research Analysis
Three impactful studies shape perioperative care: (1) a 20-year cohort (n=1,023) shows monocyte HLA-DR trajectories robustly stratify immunosuppression and outcomes in septic shock; (2) a double-blind RCT finds no added analgesic benefit from adding rectus sheath block to pecto-intercostal fascial plane blocks after cardiac surgery; (3) a propensity-matched analysis of 291,051 elective non-cardiac surgeries links afternoon start times with higher mortality, complications, ICU use, and transfusio
Summary
Three impactful studies shape perioperative care: (1) a 20-year cohort (n=1,023) shows monocyte HLA-DR trajectories robustly stratify immunosuppression and outcomes in septic shock; (2) a double-blind RCT finds no added analgesic benefit from adding rectus sheath block to pecto-intercostal fascial plane blocks after cardiac surgery; (3) a propensity-matched analysis of 291,051 elective non-cardiac surgeries links afternoon start times with higher mortality, complications, ICU use, and transfusions.
Research Themes
- Immune monitoring and enrichment strategies in sepsis
- Effectiveness of regional anesthesia techniques in cardiac surgery
- Perioperative systems and scheduling effects on surgical outcomes
Selected Articles
1. Monocyte HLA-DR expression in septic shock patients: insights from a 20-year real-world cohort of 1023 cases.
In a 20-year cohort of 1,023 septic shock patients, low mHLA-DR (<8000 AB/C) and, particularly, persistently suppressed trajectories were strongly associated with higher 28-/90-day mortality and ICU-acquired infections. Early downregulation may be adaptive, but delayed/persistent immunosuppression signaled worse outcomes, underscoring the need for serial mHLA-DR monitoring to enrich immunostimulatory trials.
Impact: This large real-world dataset validates mHLA-DR as a robust enrichment biomarker for sepsis-induced immunosuppression and clarifies the prognostic value of temporal trajectories, informing patient selection and timing for immunostimulatory therapies.
Clinical Implications: Implement serial mHLA-DR monitoring beyond initial ICU days to identify patients with persistent immunosuppression for immunostimulant trials or targeted adjuncts, and avoid relying on single early measurements that may miss late immunosuppression.
Key Findings
- Low mHLA-DR (<8000 AB/C) was associated with increased day-28 and day-90 mortality and ICU-acquired infections.
- Trajectory analysis showed persistent mHLA-DR suppression linked to worse outcomes, whereas early downregulation may be physiologic.
- Associations were consistent across static/dynamic measures, multivariable models, Kaplan–Meier curves, and K-means trajectory clustering.
Methodological Strengths
- Large real-world cohort over 20 years (n=1,023) with standardized flow cytometry.
- Multiple complementary analyses including multivariable adjustment, survival curves, and trajectory clustering.
Limitations
- Observational design limits causal inference and residual confounding may persist.
- Findings center on a single biomarker and may vary with laboratory platforms or protocols.
Future Directions: Prospective interventional trials using mHLA-DR trajectory-based enrichment; define optimal thresholds/timing for immunostimulation; integrate multi-omics immune profiling.
PURPOSE: Septic patients simultaneously experience hyperinflammation and immunosuppression, the latter driving ICU-acquired infections, prolonged stays in ICU, and increased mortality. As immunostimulant therapies enter clinical trials, effective stratification is critical to identify patients with the most profound immune dysfunction. Monocyte HLA-DR expression (mHLA-DR) has emerged as the most reliable and actionable biomarker of sepsis-induced immunosuppression. METHODS: We conducted a real-world, 20-year cohort study of 1023 septic shock patients, measuring mHLA-DR by standardized flow cytometry during the first week of ICU admission. Primary outcomes included day-28 and day-90 mortality, and ICU-acquired infections. RESULTS: Low mHLA-DR (< 8000 AB/C, a threshold already used in phase II trials) was significantly associated with increased mortality and ICU-acquired infections. This association held across static and dynamic measures, multivariate analyses, Kaplan-Meier survival curves, and trajectory clustering (K-means).
2. Pecto-intercostal fascial plane block with or without rectus sheath block in cardiac surgery: a prospective, randomized, double-blind placebo-controlled study.
Adding bilateral rectus sheath block to bilateral pecto-intercostal fascial plane blocks did not reduce pain at rest or with deep breathing in the first 24 hours post–cardiac surgery. Secondary outcomes, including opioid use, incentive spirometry, extubation time, and length of stay, were also unchanged.
Impact: A pragmatic, double-blind RCT provides high-quality negative evidence that can streamline analgesic protocols by avoiding an additional block without benefit.
Clinical Implications: Routine addition of rectus sheath block to pecto-intercostal fascial plane blocks for cardiac surgery with subxiphoid chest tubes is unlikely to improve analgesia or recovery and may be omitted to reduce procedure time and risk.
Key Findings
- No significant difference in 24-hour pain AUC at rest (93.37 vs 86.11; p=0.51) or with deep breathing (135.55 vs 128.78; p=0.57).
- Opioid consumption at 24 and 48 hours, incentive spirometry, time to extubation, ICU/hospital length of stay, and QoR-15 did not differ.
- All blocks were successfully administered with no block-related complications; trial procedures were feasible and safe.
Methodological Strengths
- Randomized, double-blind, placebo-controlled design with clearly defined primary and secondary outcomes.
- Standardized application of regional blocks and comprehensive perioperative endpoint assessment.
Limitations
- Single-center study with a modest sample size (n=62), potentially underpowered for small effects.
- Findings specific to subxiphoid chest tube insertion; generalizability to other tube positions or dosing regimens is uncertain.
Future Directions: Larger, multicenter RCTs to test alternative block combinations, dosing volumes, or catheters; explore patient subgroups and different chest tube positions.
BACKGROUND: Median sternotomy and chest tube sites drive pain following cardiac surgery. Prior research has demonstrated that pecto-intercostal fascial plane blocks (PIFBs) reduce median sternotomy pain after cardiac surgery. Prior studies examining the addition of a rectus sheath block (RSB) to localize the insertion site of subxiphoid chest tubes have had mixed results. METHODS: In this single-center, randomized, double-blind, placebo-controlled trial, 62 patients undergoing cardiac surgery with median sternotomy and subxiphoid chest tubes were randomized to receive PIFB and RSB with local anesthetic versus PIFB with local anesthetic and RSB with saline placebo. The primary outcome was pain at rest and with deep breathing in the first 24 hours after surgery. Secondary outcomes included total opioid consumption at 24 and 48 hours, performance on incentive spirometry in the first 24 hours, time to extubation, hospital and intensive care unit length of stay, and Quality of Recovery-15 score. RESULTS: There was no statistically significant difference between groups for the primary outcome, with mean area under the curve (AUC) for pain at rest in the first 24 hours 93.37±41.38 (sample mean±sample SD) in the placebo group versus 86.11±42.78 in the bupivacaine group (p=0.51), and mean AUC for pain with deep breathing 135.55±43.74 in the placebo group versus 128.78±47.08 in the bupivacaine group (p=0.57).
3. Association between surgical start time and postoperative mortality, morbidity and healthcare utilisation in elective non-cardiac surgeries: a retrospective, single-centre study using propensity score matching.
In 291,051 elective non-cardiac surgeries, afternoon starts were independently associated with higher 30-day and 1-year mortality, more complications, ICU admissions, and intra-operative transfusions compared with morning starts, even after propensity score matching and restricted mean survival time analyses. Effects were amplified in high-risk subgroups and varied by surgery type.
Impact: This large, methodologically robust analysis highlights surgical start time as a modifiable systems-level factor linked to outcomes, informing scheduling policies and resource allocation.
Clinical Implications: Consider prioritizing high-risk patients for morning start times, review staffing/case-mix patterns in the afternoon, and integrate start-time risk into perioperative risk models and quality improvement initiatives.
Key Findings
- After propensity score matching, afternoon surgeries had higher 30-day mortality (0.17% vs 0.12%, p=0.015) and 1-year mortality (3.36% vs 2.73%, p<0.001).
- Composite complications (5.94% vs 5.48%, p=0.003), ICU admissions (7.18% vs 5.87%, p<0.001), and intra-operative transfusions (4.10% vs 3.40%, p<0.001) were increased in the afternoon.
- Adjusted hazard ratios indicated elevated risk with afternoon starts (30-day mortality aHR 1.33; 1-year aHR 1.26) and shorter restricted mean survival time; effects were stronger in high-risk patients.
Methodological Strengths
- Very large cohort with propensity score matching and restricted mean survival time analysis.
- Comprehensive subgroup analyses by risk status, weekday, season, and surgery type.
Limitations
- Single-center retrospective design limits generalizability and causal inference.
- Potential unmeasured confounding (e.g., staffing patterns, case complexity clustering) cannot be excluded.
Future Directions: Multicenter prospective studies to disentangle mechanisms (e.g., workflow fatigue, staffing), evaluate interventions (morning prioritization, staffing optimization), and incorporate start time into predictive models.
INTRODUCTION: There is limited knowledge regarding the impact of surgical start time on postoperative outcomes in elective non-cardiac surgery. This study investigated the association between surgical start time and surgical outcomes in elective non-cardiac surgeries, including mortality; morbidity; and healthcare utilisation. METHODS: We analysed 291,051 patients who underwent non-cardiac surgery. Patients were grouped by surgical start time: morning (08:00-13:00) vs. afternoon (13:00-18:00). Restricted mean survival time was calculated to assess survival differences. Outcomes were also stratified by weekday and season. Subgroup analyses evaluated associations between surgical timing and outcomes in high-risk populations, including older adults. RESULTS: After propensity score matching, statistically significant differences were observed between the morning and afternoon groups for 30-day mortality (0.12% vs. 0.17%, p = 0.015); 1-year mortality (2.73% vs. 3.36%, p < 0.001); composite complications (5.48% vs. 5.94%, p = 0.003); ICU admissions (5.87% vs. 7.18%, p < 0.001); and intra-operative transfusions (3.40% vs. 4.10%, p < 0.001).