Daily Anesthesiology Research Analysis
Three perioperative studies stand out today: a 31‑trial meta-analysis finds no benefit of high inspired oxygen (FiO2) on length of stay or complications and suggests possible increased atelectasis; a randomized trial shows splenic artery ligation lowers posthepatectomy liver failure when portal pressure is high; and a nationwide analysis of 28.3 million surgeries quantifies the mortality burden of specific perioperative organ injuries, prioritizing prevention targets.
Summary
Three perioperative studies stand out today: a 31‑trial meta-analysis finds no benefit of high inspired oxygen (FiO2) on length of stay or complications and suggests possible increased atelectasis; a randomized trial shows splenic artery ligation lowers posthepatectomy liver failure when portal pressure is high; and a nationwide analysis of 28.3 million surgeries quantifies the mortality burden of specific perioperative organ injuries, prioritizing prevention targets.
Research Themes
- Perioperative oxygen strategy and postoperative outcomes
- Portal flow modulation to prevent posthepatectomy liver failure
- Population-scale risk stratification for perioperative organ injury
Selected Articles
1. Effects of high vs. low perioperative inspired oxygen fraction on length of hospital stay and postoperative complications: a systematic review, meta-analysis, and trial sequential analysis.
Across 31 RCTs (10,506 patients), high versus low FiO2 did not change length of stay, postoperative organ complications, SSI, or mortality; trial sequential analysis indicated sufficient information size for the primary outcome. Sensitivity analysis suggested high FiO2 may increase postoperative atelectasis.
Impact: Challenges guideline-endorsed high FiO2 use by showing no clinical benefit and a signal for harm (atelectasis) across diverse surgeries, with robust meta-analytic and TSA methodology.
Clinical Implications: Routine use of high FiO2 to prevent SSI should be reconsidered; individualized oxygen titration to normoxia and vigilance for atelectasis may be safer.
Key Findings
- No difference in length of hospital stay between high and low FiO2 (MD -0.01 days; 95% CI -0.10 to 0.08).
- No significant differences in postoperative cardiac, cerebral, renal, or pulmonary complications, SSI, or mortality.
- Trial sequential analysis indicated the primary outcome evidence is conclusive; sensitivity analysis suggested high FiO2 may increase postoperative atelectasis.
Methodological Strengths
- Included 31 randomized controlled trials with 10,506 participants across diverse surgeries.
- Employed random-effects meta-analysis and trial sequential analysis to assess conclusiveness.
Limitations
- Heterogeneity in FiO2 protocols and timing across trials may dilute subgroup effects.
- Signal for atelectasis depended on sensitivity analysis excluding a single study.
Future Directions: Patient-level meta-analyses and RCTs comparing titrated normoxia vs. liberal oxygen with standardized lung-protective strategies to clarify atelectasis risk and benefit-risk tradeoffs.
2. Impact of perioperative organ injury on morbidity and mortality in 28 million surgical patients.
In a nationwide cohort of 28.3 million surgeries, perioperative organ injury occurred in 4.4% and was associated with ninefold higher odds of death and 11.2 additional hospital days. Incidence and mortality varied by organ injury type, with acute kidney injury most frequent and liver injury carrying the highest mortality.
Impact: Provides population-scale quantification of the burden of perioperative organ injuries, enabling data-driven prioritization of prevention and quality-improvement initiatives across perioperative care.
Clinical Implications: Perioperative programs should target high-burden, high-mortality injuries (e.g., AKI, ARDS, liver injury) with specific bundles and monitoring; risk stratification and early detection protocols can be aligned with these quantified risks.
Key Findings
- Among 28,350,953 surgeries, perioperative organ injury occurred in 4.4% and increased odds of death ninefold.
- Organ injury prolonged hospitalization by an average of 11.2 days.
- Acute kidney injury was most frequent (2.0%, 25.0% mortality), while liver injury, though rarer (0.1%), had the highest mortality (68.7%).
Methodological Strengths
- Nationwide, comprehensive cohort including all elective and emergent surgeries over four years.
- Granular reporting of incidence and mortality across multiple organ injury types.
Limitations
- Administrative data subject to coding errors and residual confounding; causal inference is limited.
- Lack of granular intraoperative variables (e.g., fluids, hemodynamics) that may mediate risk.
Future Directions: Linkage with intraoperative physiologic and therapy data to identify modifiable drivers; prospective implementation of targeted prevention bundles and evaluation via learning health systems.
3. Portal flow modulation by splenic artery ligation to prevent posthepatectomy liver failure: A randomized controlled trial.
In hepatectomy patients with portal venous pressure >15 mm Hg, splenic artery ligation lowered portal pressures and reduced clinically significant posthepatectomy liver failure (16.7% vs 66.7%), ascites burden, and comprehensive complication index in a randomized trial halted early for benefit.
Impact: Introduces a simple, physiology‑targeted intraoperative maneuver that significantly reduces posthepatectomy liver failure in high‑risk patients, with immediate translational relevance.
Clinical Implications: In patients with elevated intraoperative portal venous pressure, splenic artery ligation can be considered to modulate portal inflow and reduce PHLF; requires team protocols for pressure monitoring and selection.
Key Findings
- Among patients with portal venous pressure >15 mm Hg, splenic artery ligation reduced PHLF grades B/C from 66.7% to 16.7% (P = .006).
- Significant reductions in portal venous pressure and PVP–CVP gradient compared with control and pre-ligation values.
- Lower comprehensive complication index (8.70 vs 20.90) and reduced ascites volume with ligation.
Methodological Strengths
- Randomized controlled design targeting a physiologically defined high-risk subgroup (PVP >15 mm Hg).
- Clinically meaningful composite outcomes (PHLF B/C, CCI, ascites) with consistent benefit.
Limitations
- Single-center trial with early termination and small randomized sample, which may overestimate effect sizes.
- Generalizability limited to patients with measured elevated portal venous pressure undergoing open hepatectomy.
Future Directions: Multicenter RCTs with standardized portal pressure monitoring, assessment of long-term outcomes, and integration with other inflow modulation strategies.