[Risk of postoperative delirium in older adults under balanced general anesthesia]

Rev Med Inst Mex Seguro Soc. 2024 Nov 4;62(6):1-8. doi: 10.5281/zenodo.13381460.
[Article in Spanish]

Abstract

Background: Anesthetic depth can influence the incidence of postoperative delirium (POD). This depth is related to the potency of the volatile anesthetics used to maintain balanced general anesthesia. This potency is measured by means of the minimum alveolar concentration (MAC). In older adults, it is unknown which MAC is associated with the risk of POD.

Objective: To estimate the risk of POD associated with minimum alveolar concentration (MAC) levels of volatile anesthetics in older adults who received balanced general anesthesia.

Material and methods: A prospective cohort study was carried out with 119 patients, aged ≥ 60 years, with 0 points in the 4 "As" test (4AT), without neurological or psychiatric diseases. During the intraoperative period, the CAM provided was recorded, and in the postoperative period, the presence of emergency with delirium and/or POD was evaluated at 2 and 24 hours, considering a score ≥ 4.

Results: A longer hospital stay was found in the group that received a MAC ≥0.9. The incidence of POD was 29.4%. Those who received a MAC ≥ 0.9 had an RR of 2.22 (95%CI: 1.2-4.2) of presenting POD. An adjusted logistic regression model was performed with the variables female sex (OR: 4, 95%CI: 1.5-10.4), ASA physical status 3-4 (OR: 3.7, 95%CI: 1.5-9) and MAC ≥ 0.9 (OR: 3.1 95%CI: 1.2-8) with an R2: 0.26 and a constant of 3.005.

Conclusions: MAC ≥ 0.9 represents a risk factor for DPO, so individualized dosing of volatile anesthetics should be used.

Introducción: la profundidad anestésica puede influir en la incidencia del delirium posoperatorio (DPO), dicha profundidad se relaciona con la potencia de los anestésicos volátiles usados para el mantenimiento de la anestesia general balanceada. Esta potencia es medida a través de la concentración alveolar mínima (CAM). En el adulto mayor se desconoce cuál es la CAM que se asocia con el riesgo de DPO.

Objetivo: estimar el riesgo de DPO asociado a los niveles de concentración alveolar mínima (CAM) de los anestésicos volátiles en adultos mayores que recibieron anestesia general balanceada.

Material y métodos: se realizó un estudio de cohorte prospectivo, con 119 pacientes con edad ≥ 60 años, 0 puntos en la prueba 4 “As” (4AT), sin enfermedades neurológicas o psiquiátricas. Se registró la CAM proporcionada, y en el posoperatorio se evalúo la presencia de emergencia con delirium y/o DPO a las 2 y 24 horas, considerando un puntaje ≥ 4.

Resultados: se encontró una mayor estancia hospitalaria en el grupo que recibió una CAM ≥ 0.9. La incidencia del DPO fue de 29.4%. Los que recibieron una CAM ≥ 0.9 presentaron RR de 2.22 (IC95%: 1.2-4.2) de presentar DPO. Se realizó un modelo de regresión logística ajustado con las variables sexo femenino (RM: 4, IC95%: 1.5-10.4), estado físico ASA 3-4 (RM: 3.7, IC95%: 1.5-9) y CAM ≥ 0.9 (RM: 3.1, IC95%: 1.2-8) con un R2 de 0.26 y una constante de 3.005.

Conclusiones: la CAM ≥ 0.9 representa un factor de riesgo para DPO, por lo que se debe hacer uso de la dosificación individualizada de los anestésicos volátiles.

Keywords: Aged; Anesthesia, General; Cohort Studies; Emergence Delirium.

Publication types

  • English Abstract

MeSH terms

  • Aged
  • Aged, 80 and over
  • Anesthesia, General* / adverse effects
  • Anesthetics, Inhalation / adverse effects
  • Delirium / chemically induced
  • Delirium / epidemiology
  • Delirium / etiology
  • Emergence Delirium / diagnosis
  • Emergence Delirium / epidemiology
  • Emergence Delirium / etiology
  • Female
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Postoperative Complications / epidemiology
  • Postoperative Complications / etiology
  • Prospective Studies
  • Risk Assessment
  • Risk Factors

Substances

  • Anesthetics, Inhalation