Daily Anesthesiology Research Analysis
Three impactful anesthesia studies advance perioperative safety and analgesia. A large RCT shows subglottic jet ventilation reduces hypoxia during flexible bronchoscopy, a randomized crossover trial demonstrates head-elevated positioning expedites GlideScope intubation under cervical immobilization, and a network meta-analysis identifies ESPB plus PCA as the most effective opioid-sparing strategy after cardiac surgery via sternotomy.
Summary
Three impactful anesthesia studies advance perioperative safety and analgesia. A large RCT shows subglottic jet ventilation reduces hypoxia during flexible bronchoscopy, a randomized crossover trial demonstrates head-elevated positioning expedites GlideScope intubation under cervical immobilization, and a network meta-analysis identifies ESPB plus PCA as the most effective opioid-sparing strategy after cardiac surgery via sternotomy.
Research Themes
- Airway management optimization under challenging conditions
- Hypoxia prevention strategies during flexible bronchoscopy
- Opioid-sparing regional anesthesia for cardiac surgery
Selected Articles
1. Subglottic jet ventilation versus supraglottic jet ventilation for flexible bronchoscopy: a randomized controlled trial.
In 352 sedated bronchoscopy patients, subglottic jet ventilation significantly lowered hypoxia and severe hypoxia compared with supraglottic jet ventilation, reduced airway rescue maneuvers, and eliminated gastric insufflation events. Safety profiles were otherwise similar.
Impact: Defines a more effective oxygenation strategy during flexible bronchoscopy, addressing a common cause of intra-procedural instability. The pragmatic RCT supports immediate practice change.
Clinical Implications: Prefer subglottic jet ventilation via a dedicated introducer for bronchoscopy under moderate-to-deep sedation to reduce hypoxia and gastric insufflation; prepare fewer airway rescue maneuvers.
Key Findings
- Hypoxia incidence reduced from 16.6% to 6.0% with subglottic jet ventilation (RR 0.364, 95% CI 0.18–0.72; P=0.002).
- Severe hypoxia reduced (3.0% vs 8.6%; RR 0.351, 95% CI 0.12–0.95; P=0.030).
- Fewer airway rescue maneuvers: jaw thrust (4.8% vs 12.9%) and mask ventilation (2.4% vs 7.4%).
- No gastric insufflation with subglottic versus 31 events with supraglottic (P<0.001).
Methodological Strengths
- Randomized controlled design with a large sample (n=352).
- Clinically meaningful primary endpoint (hypoxia) and prespecified secondary outcomes.
Limitations
- Single-center study may limit generalizability.
- Device- and protocol-specific implementation (SEEK introducer) may affect external adoption.
Future Directions: Multicenter trials to confirm effectiveness across bronchoscopy indications and sedation strategies; evaluation of CO2 clearance and long-term safety.
BACKGROUND: Jet ventilation technique can be used to supply oxygen to prevent hypoxia for patients undergoing flexible bronchoscopy. An optimal access route for jet ventilation technique during flexible bronchoscopy has not been determined. Our aim was to compare the effectiveness and safety of subglottic jet ventilation via a new introducer (Safe Easy Endotracheal Kit-flexible, SEEK METHODS: This was a single-center randomized controlled trial. 352 patients scheduled to undergo flexible bronchoscopy under moderate-to-deep sedation were randomly assigned to the following two groups: the subglottic jet ventilation group, and the supraglottic jet ventilation group. The primary outcome was hypoxia during flexible bronchoscopy. RESULTS: Subglottic jet ventilation decreased the incidence of hypoxia from 16.6% to 6.0% compared with supraglottic jet ventilation [relative risk (RR) for hypoxia, 0.364, 95% CI 0.18 to 0.72; P 0.002]. The incidence of severe hypoxia was also significantly diminished in the subglottic jet ventilation group compared with the supraglottic jet ventilation group (3% vs. 8.6%; RR 0.351, 95% CI 0.12 to 0.95; P 0.030). The subglottic jet ventilation group needed significantly less jaw thrust (4.8% vs. 12.9%; RR 0.374, 95% CI 0.17 to 0.82; P 0.010), and mask ventilation (2.4% vs. 7.4%; RR 0.327, 95% CI 0.10 to 0.99; P 0.037). No gastric insufflation occurred in the subglottic jet ventilation group, 31 instances occurred in the supraglottic jet ventilation group (P < 0.001). There was no significant difference between the two groups in terms of other adverse events including xerostomia, pharyngalgia, nasal bleeding. CONCLUSIONS: Subglottic jet ventilation more effectively reduces the incidence of hypoxia in patients undergoing flexible bronchoscopy under moderate-to-deep sedation when compared with supraglottic jet ventilation. Subglottic jet ventilation via the SEEK TRIAL REGISTRATION: ChiCTR2300076139.
2. Effect of head-elevated versus neutral position on tracheal intubation using a hyper-angulated video laryngoscope under cervical spine immobilization: a randomised crossover trial.
Head-elevated positioning aligned to the ear–sternal notch shortened GlideScope intubation time by a median 4.5 seconds, reduced difficulty and optimization maneuvers, and improved laryngeal visualization under cervical immobilization.
Impact: Provides an immediately actionable positioning intervention to improve airway management in high-risk cervical immobilization scenarios with hyper-angulated videolaryngoscopy.
Clinical Implications: Adopt head-elevated positioning (ear-to-sternal notch alignment) when using hyper-angulated videolaryngoscopes under MILS to improve glottic view, reduce optimization maneuvers, and expedite intubation.
Key Findings
- Median intubation time shorter with head-elevated vs neutral: 27.2 vs 31.5 seconds (P=0.001).
- Lower modified intubation difficulty scale with head-elevated (median 1 vs 2; P<0.001).
- Fewer optimization maneuvers for blade insertion (5.6% vs 13.9%) and tube advancement (31.8% vs 58.4%).
- Superior laryngeal view: higher POGO score and more favorable modified Cormack-Lehane grades.
Methodological Strengths
- Randomised crossover design controlling inter-individual variability.
- Comprehensive performance metrics including time, difficulty, maneuvers, and visualization.
Limitations
- Single-country, elective surgery population; results may not generalize to emergency airways.
- Clinical outcomes beyond immediate intubation performance (hypoxia, trauma) were not primary endpoints.
Future Directions: Evaluate head-elevated positioning in emergency airway scenarios and in patients with predicted difficult airways; assess downstream clinical outcomes.
BACKGROUND: Videolaryngoscopes with hyper-angulated blades improve glottic visualisation in patients with cervical spine immobilisation but may complicate blade insertion and tracheal tube (TT) advancement. We compared the head-elevated (HE) and head-neutral (HN) position during GlideScope®-guided intubation under manual in-line stabilisation (MILS). METHODS: In this randomised crossover trial, 180 adult patients undergoing elective surgery were allocated to HN or HE groups. Under MILS, videolaryngoscopy was performed in both positions, but intubation was attempted only in the second designed position. The HE position was achieved by elevating the back section of the table to align the external auditory meatus and sternal notch. RESULTS: Intubation was attempted in 177 patients with 100% success. Median intubation time was shorter in HE group than HN group (27.2 [23.4-34.3] vs. 31.5 [27.0-40.5] s; difference -4.5 s, 95% CI -7.5 to -1.8; P = 0.001). The modified intubation difficulty scale was lower in HE group (1 [0-1]) than HN group (2 [1-3]; P < 0.001). The need for optimisation manoeuvres was less frequent in the HE position for GlideScope® blade insertion (5.6% vs. 13.9%; P = 0.0001) and for TT advancement (31.8% vs. 58.4%; P < 0.001). Laryngeal view was superior in the HE position, with a higher mean percentage of glottic opening score (42.9 ± 35.6% vs. 26.8 ± 32.3%; P < 0.0001) and a greater proportion of easy modified Cormack-Lehane grades (83.8% vs. 64.8%; P < 0.0001). CONCLUSION: The HE position significantly improved intubation efficiency and technical ease using a hyper-angulated videolaryngoscope under MILS. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05671978.
3. Comparative efficacy of chest wall fascial plane blocks for cardiac surgery via median sternotomy: a network meta-analysis.
Across 24 RCTs, ESPB combined with PCA ranked best for reducing 24-hour opioid consumption after sternotomy, with moderate GRADE confidence. Meta-regression implicated local anesthetic type/volume, timing, and continuous techniques as modifiers of efficacy.
Impact: Provides comparative effectiveness evidence to guide block selection for cardiac surgery, supporting opioid stewardship and enhanced recovery pathways.
Clinical Implications: Consider ESPB with PCA as a preferred strategy for sternotomy analgesia; tailor protocols by optimizing local anesthetic type/volume, timing, and continuous techniques.
Key Findings
- ESPB plus PCA ranked highest in reducing 24-hour morphine equivalents versus PCA alone (moderate GRADE confidence).
- No consistent superiority on early pain scores, but trends favored ESPB in several time points.
- Meta-regression suggests efficacy is influenced by local anesthetic type/volume, injection timing, and continuous block use.
Methodological Strengths
- PRISMA-NMA compliant network meta-analysis with GRADE appraisal.
- Inclusion of 24 RCTs with primary outcome harmonized to morphine equivalents.
Limitations
- Heterogeneity across trials (block protocols, anesthetics, timing) limits certainty.
- Moderate confidence; some outcomes had fewer contributing studies and wide intervals.
Future Directions: Head-to-head multicenter RCTs comparing optimized ESPB protocols versus alternative blocks; standardized dosing and continuous techniques.
BACKGROUND: To quantitatively evaluate and compare the relative efficacy of different chest wall fascial plane blocks in cardiac surgery via median sternotomy. METHOD: This study was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses for Network Meta-Analyses (PRISMA-NMA) utilizing a frequentist network meta-analysis (NMA) method. Conclusions were drawn using a minimally contextualized framework of the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. RESULTS: Twenty-four randomized controlled trials were retrieved from four databases. A total of 1366 adult patients were included, of whom 789 (57.8%) received one of five chest wall fascial plane block modalities. The primary outcome was 24-hour postoperative opioid consumption (converted as intravenous morphine in mg, n = 1159). With moderate confidence, erector spinae plane block (ESPB) plus patient-controlled analgesia (PCA) was more efficacious in reducing 24-hour postoperative intravenous morphine than PCA alone (Rank based on SUCRA = 1). Secondary outcomes included postoperative mechanical ventilation time and pain assessment scores (0, 12, and 24 h after extubation) with 1186, 664, 1054, and 958 patients analyzed, respectively. Network meta-regression results across primary or secondary outcomes suggested that local anesthetic type and volume, injection timing, and a continuous block feature may contribute to the relative efficacy of chest wall fascial plane blocks. CONCLUSIONS: ESPB plus PCA was found to be more efficacious in decreasing postoperative opioid requirements for adults undergoing cardiac surgery via median sternotomy, with moderate confidence in the current evidence. Modifying the current fascial plane block protocols may be the direction of future clinical studies. TRIAL REGISTRATION: PROSPERO identifier CRD42022345047.