Publish in this journal
Journal Information
La versión en español de este artículo estará disponible en breve
Download PDF
More article options
Not available
Original article
Available online 13 May 2022
Bispectral index and suppression ratio after cardiac arrest: are they useful as bedside tools for rational treatment escalation plans?
Índice biespectral y tasa de supresión tras parada cardiaca: ¿son útiles para individualizar planes de escalada terapéutica?
Emilio Arbas-Redondoa,
Corresponding author

Corresponding author.
, Sandra O. Rosillo-Rodríguezb,c, Carlos Merino-Argosa, Irene Marco-Clementa, Laura Rodríguez-Soteloa, Luis A. Martínez-Marína, Lorena Martín-Poloa, Andrea Vélez-Salasa, Juan Caro-Codónb,c, Daniel García-Arribasb, Eduardo Armada-Romerob,c, Esteban López-De-Sab,c
a Servicio de Cardiología, Hospital Universitario La Paz, Madrid, Spain
b Unidad de Cuidados Agudos Cardiovasculares, Servicio de Cardiología, Hospital Universitario La Paz, Madrid, Spain
c Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
Received 18 November 2021. Accepted 15 March 2022
Article information
Full Text
Download PDF
Figures (5)
Show moreShow less
Tables (4)
Table 1. Demographics, baseline and cardiac arrest-related variables of all patients included in the study and differences between the PC 1-2 and CPC 3-5 groups
Table 2. Main causes of death in survivors of cardiac arrest beyond the first 48hours of admission and within the 3-month follow-up
Table 3. Outcomes of average BIS and SR values during first 48hours of targeted temperature management after cardiac arrest according to neurological function
Table 4. Predictive performance of average BIS and SR during the first 6, 12 and 24hours of TTM for neurological prognostication
Show moreShow less
Additional material (1)
Introduction and objectives

Myocardial dysfunction contributes to early mortality (24-72 hours) among survivors of a cardiac arrest (CA). The benefits of mechanical support in refractory shock should be balanced against the patient's potential for neurological recovery. To date, these early treatment decisions have been taken based on limited information leading mainly to undertreatment. Therefore, there is a need for early, reliable, accessible, and simple tools that offer information on the possibilities of neurological improvement.


We collected data from bispectral index (BIS) and suppression ratio (SR) monitoring of adult comatose survivors of CA managed with targeted temperature management (TTM). Neurological status was assessed according to the Cerebral Performance Category (CPC) scale.


We included 340 patients. At the first full neurological evaluation, 211 patients (62.1%) achieved good outcome or CPC 1-2. Mean BIS values were significantly higher and median SR lower in patients with CPC 1-2. An average BIS> 26 during first 12 hours of TTM predicted good outcome with 89.5% sensitivity and 75.8% specificity (AUC of 0.869), while average SR values> 24 during the first 12 hours of TTM predicted poor outcome (CPC 3-5) with 91.5% sensitivity and 81.8% specificity (AUC, 0.906). Hourly BIS and SR values exhibited good predictive performance (AUC> 0.85), as soon as hour 2 for SR and hour 4 for BIS.


BIS/SR are associated with patients’ potential for neurological recovery after CA. This finding could help to create awareness of the possibility of a better outcome in patients who might otherwise be wrongly considered as nonviable and to establish personalized treatment escalation plans.

Cardiac arrest
Post-cardiac arrest syndrome
Consciousness monitors
Bispectral index
Suppression ratio
Neurological prognostication
Introducción y objetivos

La disfunción miocárdica contribuye a la mortalidad precoz (24-72 horas) de los supervivientes de parada cardiaca (PC). Actualmente, la decisión de implantar un dispositivo de soporte circulatorio en este contexto se toma con información limitada acerca del potencial de recuperación neurológica (PRN) del paciente, lo que en muchas ocasiones termina en infratratamiento. Por tanto, requerimos de herramientas accesibles y fiables que añadan información sobre el PRN y ayuden a establecer planes individualizados de escalada terapéutica.


Se recogieron valores de índice biespectral (BIS) y tasa de supresión (TS) en supervivientes de una PC sometidos a control de la temperatura corporal. La función neurológica se evaluó con la escala Cerebral Performance Category (CPC).


Se incluyeron 340 pacientes. En la primera evaluación neurológica completa, 211 (62,1%) alcanzaron buen pronóstico (CPC 1-2). Los valores de BIS fueron significativamente mayores y los de TS menores, en pacientes con CPC 1-2. Un BIS promedio> 26 en las primeras 12 horas predijo buena evolución neurológica (sensibilidad 89,5%; especificidad 75,8%; AUC=0,869), mientras que una TS promedio> 24 en las primeras 12 horas predijo mala evolución o CPC 3-5 (sensibilidad 91,5%; especificidad 81,8%; AUC=0,906). Los valores horarios de BIS/TS mostraron buena capacidad predictiva (AUC> 0,85) desde la 2.ª hora para TS y 4.ª para BIS.


El BIS/TS permiten estimar el PRN tras una PC. Este hallazgo puede contribuir a crear conciencia con respecto a evitar la limitación de escalada terapéutica en pacientes potencialmente recuperables.

Palabras clave:
Parada cardiorrespiratoria
Síndrome de paro postcardiaco
Hipotermia inducida
Monitores de consciencia
Índice biespectral
Tasa de supresión
Pronóstico neurológico


These are the options to access the full texts of the publication Revista Española de Cardiología (English Edition)
Members of SEC
Use the Society's website login and password here

If you already have your login data, please click here .

If you have forgotten your password you can you can recover it by clicking here and selecting the option “I have forgotten my password”
Subscribe to

Revista Española de Cardiología (English Edition)

Purchase article

Purchasing article the PDF version will be downloaded

Price 19.34 €

Purchase now
Phone for subscriptions and reporting of errors
From Monday to Friday from 9 a.m. to 6 p.m. (GMT + 1) except for the months of July and August which will be from 9 a.m. to 3 p.m.
Calls from Spain
932 415 960
Calls from outside Spain
+34 932 415 960
Revista Española de Cardiología (English Edition)

Subscribe to our newsletter

View newsletter history
Article options
Supplemental materials
es en

¿Es usted profesional sanitario apto para prescribir o dispensar medicamentos?

Are you a health professional able to prescribe or dispense drugs?