The optimum duration of low molecular weight heparin for thromboembolism prevention in high risk orthopedic surgery
Bibliographic record
Abstract
ABSTRACT For patients undergoing hip and knee surgery, the optimum duration of prophylaxis with Low Molecular Weight Heparin (LMWH) is controversial. This paper takes a critical look at the evidence for extending the duration of administration of LMWH beyond the currently recommended 7 to 10 days. Among the papers reviewed the only consistent benefit associated with prolonged LMWH prophylaxis (duration of 4 to 5 weeks post operatively) was a reduction in venographically detected deep vein thrombosis. Clinically relevant endpoints such as symptomatic thromboembolism (2 to 18%), pulmona1y embolus (less than 7%) and death (less than 1%) were unaffected by extending the administration of LMWH. Unanswered questions remain about the safety of 4 to 5 weeks of LMWH at doses used in Canada for this indication. Extended LMWH prophylaxis increases drug costs by approximately 3-fold. The added expense is $153 to $254 per patient depending on the medication used. The cost effectiveness of prolonged LMWH prophylaxis relative to the current recommended duration has not been determined. In summary, continued prophylaxis with a LMWH beyond 7 to 10 days should not be widely endorsed until it can be demonstrated that the regimen provides clinical benefits at a reasonable cost. RESUME La duree maximale du traitement prophylactique a l'heparine de faible poids moleculaire (HFPM) chez les patients qui doivent subir une chirurgie du genou ou de la hanche est controversee. Cet article brosse un portrait critique des observations sur lesquelles on se fonde pour prolonger la duree du traitement a l'HFPM au-dela des 7 a 10 jours actuellement recommandes. Parmi les articles passes en revue, le seul avantage recurrent associe au traitement prophylactique prolonge a l'HFPM (duree de 4 a 5 semaines apres l'operation) etait une diminution des thromboses veineuses profondes visibles a la venographie. Les parametres pertinents du point de vue clinique, telles la thromboembolie symptomatique (2 a 18 %), l'embolie pulmonaire (moins de 7 %) et la mortalite (moins de l %) n'ont pas ete affectes par la prolongation de la duree du traitement a l'HFPM. Des questions demeurent toujours sans reponse relativement a l'innocuite du traitement a l'HFPM d'une duree de 4 a 5 semaines, aux closes utilisees au Canada pour cette indication. Le traitement prophylactique a l'HFPM accroit le cout des traitements medicamenteux d'un facteur d'environ 3. Les depenses supplementaires se chiffrent a 153 a 254 $ par patient, selon le medicament utilise. Le rapport cout/efficacite du traitement prophylactique a l'HFPM quant a la duree actuelle recommandee n'a pas ete etabli. En resume, le traitement prophylactique de longue duree a l'HFPM au-dela de 7 a 10 jours ne devrait pas etre utilise systematiquement, du moins jusqu'a ce que des etudes aient demontre que cc regime therapeutique offre des avantages cliniques a un cout raisonnable.
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 | 0.002 | 0.007 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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".