EP180 Continuous deep serratus anterior plane block for sternotomy analgesia following cardiac surgery: a randomized, placebo-controlled, double-blinded feasibility study
Bibliographic record
Abstract
Background and Aims Moderate to severe pain is common after cardiac surgery, peaking during the first and second postoperative day. Several nerve blocks for sternotomy have been described, however the optimal location for continuous catheters has not been established. This study sought to assess the feasibility of a larger trial assessing the efficacy of serratus anterior plane (SAP) catheters for sternotomy pain. Methods This was a double-blinded trial including patients undergoing cardiac surgery via sternotomy. Bilateral SAP catheters were placed in all patients, randomized to Ropivacaine or placebo. Feasibility was assessed based on pre-determined endpoints: 1. Average recruitment rate >4 per month; 2. Protocol adherence rate >90%; 3. Primary outcome measurement rate >90%; 4. Major catheter-related adverse event rate >2%. Quality of recovery index (QoL-15) was compared using an independent t-test. Results Fifty-two patients were randomized with feasibility data for 50 (2 were withdrawn). There was a poor recruitment rate (2.4 patients per month). There were no major protocol deviations but there were minor deviations in 12% of patients. The primary outcome (QoL-15) was measured in 96% cases. QoL-15 at 72 hours was not different between groups (Ropivacaine 100 +/- 22 vs Placebo 97 +/- 18, p=0.63). The overall incidence of pneumothorax was found to be 12%. Conclusions A single-center RCT was deemed to be not feasible due to low recruitment rate. It was unclear if the pneumothorax was related to the block since there was not a no-block group. This factor needs to be explored before considering the possibility of a multi-center study. _REB approval 2021.06
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.007 | 0.004 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.004 | 0.002 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.003 | 0.002 |
| Insufficient payload (model declined to judge) | 0.006 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".