Perioperative Outcomes of Hyperlactatemia during Craniotomy: A Systematic Review and Meta-Analysis of 1,832 Patients
Bibliographic record
Abstract
Abstract Background Hyperlactatemia, is common in patients undergoing neurosurgical procedures. Several studies have identified potential risk factors for developing hyperlactatemia in neurosurgical patients, including body mass index, surgery duration, tumour volume, and certain drugs such as volatile anesthetic agents and corticosteroids. This systematic review and meta-analysis examined the evidence of the association between perioperative lactate levels in patients undergoing brain surgery and postoperative morbidity and mortality. Methods Using PubMed, Scopus, Web of Science, Embase, CINAHL, Medline, Google Scholar, and the Cochrane Central Register of Controlled Trials databases, a systematic literature search was conducted for studies examining the association between perioperative hyperlactatemia and postoperative outcomes in patients undergoing brain surgery. Two authors independently evaluated the full-text papers for eligibility, and then data extraction and meta-analyses of similar studies were conducted (using a random effect model for each outcome measure). The Newcastle Ottawa Scale was used to evaluate the risk of bias (NOS scale). Results Seven observational studies were included, and a total of 1,832 patients were assessed in the systematic review and meta-analysis. The quality of the included studies ranged from poor to high quality according to the NOS quality assessment tool. Meta-analysis results revealed no significant association between perioperative hyperlactatemia and postoperative new neurological deficits (five studies: odds ratio [OR] = 0.97, 95% confidence interval [CI] [0.50–1.87], p = 0.92; heterogeneity: I 2 = 38%, p = 0.18). Similarly, perioperative hyperlactatemia was neither significantly associated with increased 30-day postoperative mortality (two studies; OR = 0.20, 95% CI [0.02–2.00], p = 0.17; heterogeneity: I 2 = 0%, p = 0.59) nor 6 months survival rate (three studies; OR = 1.05, 95% CI [0.75–1.47], p = 0.79; heterogeneity: I 2 = 0%, p = 0.51). Moreover, there was no difference in the length of hospital stay between the two groups (four studies: mean difference = –0.85, 95% CI [–1.73 to 0.03], p = 0.06). Pooled studies were not homogenous (I 2 = 68%, p = 0.03). Conclusion Perioperative hyperlactatemia is benign in neurosurgical patients and is not associated with significant postoperative outcomes, such as developing new postoperative neurological deficit, 30-day mortality, 6-month survival, or prolonged hospital stay.
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 | 0.012 | 0.026 |
| Meta-epidemiology (narrow) | 0.003 | 0.002 |
| Meta-epidemiology (broad) | 0.018 | 0.041 |
| Bibliometrics | 0.006 | 0.007 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.002 | 0.002 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
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".