Association of Preoperative Frailty With Intraoperative Hemodynamic Instability and Postoperative Mortality
Notice bibliographique
Résumé
BACKGROUND: Frailty, a state of decreased physiological reserve, is strongly associated with perioperative mortality in older adults. However, the mechanism by which frailty is associated with mortality is not yet understood. Autonomic dysfunction in the form of decreased intraoperative hemodynamic variability has been shown to be associated with increased mortality. We aimed to see whether frail patients have less hemodynamic variability under anesthesia and whether variability mediates the relationship between frailty and 30-day mortality. METHODS: We performed a single-center retrospective study of 1223 patients ≥65 years of age undergoing surgery between July 2008 and December 2012. We used markers of frailty: age >70, preoperative body mass index <18.5, hematocrit <35%, albumin <3.4 g/dL, and creatinine >2.0 mg/dL. We modeled the outcome of 30-day mortality with number of frailty conditions adjusting for gender, length of surgery, American Society of Anesthesiologists class, and need for transfusion. Intraoperative hemodynamic variability was defined as the count of episodes of absolute change >15% in fractional mean arterial pressure (MAP) between consecutive 5-minute intervals. We evaluated the role of intraoperative hemodynamic variability as a mediator (modifier) of the relationship between frailty and mortality, checking for 3 conditions: (1) frailty must affect episodes of absolute change >15% in fractional MAP; (2) episodes of absolute change >15% in fractional MAP must affect 30-day mortality; and (3) mediation effect is significant. We used the product method, in which the mediation effect was estimated as the product of the first 2 relationships. Then we applied the percentile bootstrap method to obtain the 95% CI for the estimate of mediation effect. RESULTS: Number of frailty conditions and episodes of absolute change >15% in fractional MAP were inversely proportional. Presence of ≥4 frailty conditions was associated with >40% reduction of the number of episodes of absolute change >15% in fractional MAP. Regarding mortality, episodes of absolute change >15% in fractional MAP were protective. The addition of absolute change >15% in fractional MAP in the mortality model resulted in a decrease in the frailty odds ratio from 10.6 to 9.1 (4+ conditions), suggesting that episodes of absolute change >15% in fractional MAP are indeed a mediator. The mediation effect was modest; 5 episodes of absolute change >15% in fractional MAP was 5.2%, 6.4%, 6.9%, and 9.0% for frailty conditions from 1 to 4+, respectively. CONCLUSIONS: Frailty is associated with less intraoperative blood pressure variation, and the relationship of frailty with 30-day mortality is partially mediated by episodes of absolute change >15% in fractional MAP. This suggests that autonomic dysregulation may be a modest part of the mechanism behind the association between frailty and perioperative mortality. Our finding is consistent with recent literature, suggesting that an intact autonomic nervous system confers lower perioperative mortality.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».