Survival After Cardiac Arrest: How New Treatment Guidelines Changed Patient Outcomes. (RetroAC)

Implementation of the New Guidelines on the Management of the Patient Resuscitated From Cardiac Arrest and Impact on Survival: Retrospective Observational Study / Implementazione Delle Nuove Linee Guida Sulla Gestione Del Paziente Rianimato da Arresto Cardiaco ed Impatto Sulla Sopravvivenza: Studio Osservazionale Retrospettivo.

The goal of this retrospective observational cohort study is to evaluate whether the progressive implementation of updated post-cardiac arrest care guidelines has improved survival and neurological recovery in adult patients admitted to the intensive care unit (ICU) after successful resuscitation from cardiac arrest.

Cardiac arrest is one of the leading causes of death worldwide. More than half of patients successfully resuscitated from cardiac arrest die before hospital discharge, largely due to a complex condition known as Post-Cardiac Arrest Syndrome (PCAS), which affects the brain, heart, and all major organ systems. Over the past decade, the European Resuscitation Council (ERC) and the European Society of Intensive Care Medicine (ESICM) have published updated post-resuscitation care guidelines in 2010, 2015, and 2021, introducing progressively refined treatment recommendations. However, no study has yet evaluated whether the local adoption of these evolving guidelines has translated into measurable improvements in patient outcomes over time.

The main questions this study aims to answer are:

• Has survival to ICU discharge improved across three successive guideline periods (2010, 2015, and 2021) in adult cardiac arrest patients admitted to the ICU?
• Has neurological recovery at ICU and hospital discharge improved across the three guideline cohorts?
• What is the local level of adherence to each set of guideline recommendations, and how does it relate to patient outcomes?
• What is the impact of individual new interventions introduced by each guideline update on survival and organ function?
• Do outcomes differ based on whether the cardiac arrest occurred outside or inside the hospital, or based on its underlying cause (cardiac, respiratory, metabolic, toxicological, or traumatic)?

Researchers will compare three patient cohorts defined by the guideline period active at the time of ICU admission - Cohort A (January 2011-December 2015, treated according to 2010 guidelines), Cohort B (January 2016-March 2021, treated according to 2015 guidelines), and Cohort C (April 2021-April 2024, treated according to 2021 guidelines) - to determine whether progressive guideline implementation is associated with improved survival and neurological outcomes over time. Cohort A serves as the reference group.

Participants in this study are adult patients (aged 18 years or older) who experienced cardiac arrest of any cause - whether in or out of hospital - were successfully resuscitated, and were subsequently admitted to ICU at the S. Chiara Hospital in Trento, Italy. Data are collected retrospectively from digitized medical records and cover clinical characteristics, cardiac arrest details, ICU treatments, laboratory and imaging findings, and patient outcomes including survival, length of stay, ventilator-free days, and neurological status at discharge (assessed using the Cerebral Performance Category scale). No interventions are performed as part of this study. Patient data are fully anonymized prior to analysis.

Study Overview

• Status: Completed
• Conditions: Cardiac Arrest (CA); Post Cardiac Arrest Syndrome
• Intervention / Treatment: Other: post-resuscitation care

• Study Type: Observational
• Enrollment (Actual): 630

Contacts and Locations

Study Locations

• Italy
  • Italy
    • Trento, Italy, Italy, 38122
      • Santa Chiara Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients will be selected from the clinical records of the General Intensive Care Unit (ICU1) of S. Chiara Hospital, Trento, Italy, the main teaching hospital of the Azienda Sanitaria Universitaria Integrata del Trentino (ASUIT). S. Chiara Hospital serves as the primary referral center for critical care in the Trentino region and operates in close collaboration with Trentino Emergenza, the regional emergency medical service. Data will be retrieved from the hospital's digitized clinical records system, which is validated on an hourly basis by ward clinical staff, ensuring high data quality and completeness. The study covers a 14-year period (January 2011- December 2024), spanning three successive ERC-ESICM guideline eras. All data will be anonymized.

Description

INCLUSION CRITERIA:

• Resuscitated from cardiac arrest and subsequently admitted to the intensive care unit (ICU)
• Age ≥18 years at the time of ICU admission
• Out-of-hospital or in-hospital cardiac arrest
• Cardiac arrest of any etiology, including cardiac, respiratory, metabolic, toxicological, and traumatic causes

Exclusion Criteria:

• Age <18 years at the time of ICU admission (pediatric patients)
• Not admitted to ICU

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Cohort A - 2010 ERC Guidelines: Post-Cardiac Arrest Patients Managed per 2010 ERC Guidelines; Adult patients (≥18 years) admitted to the general ICU of S. Chiara Hospital, Trento, Italy, between January 2011 and December 2015, following successful resuscitation from in-hospital or out-of-hospital cardiac arrest of any etiology. This cohort was managed according to the 2010 ERC Guidelines, which emphasized post-resuscitation care standardization, therapeutic hypothermia (32-34°C for 24 hours), avoidance of hyperoxia, glucose control (target <180 mg/dL), and primary percutaneous coronary intervention where indicated. This cohort serves as the reference group for comparing survival and neurological recovery outcomes across the three guideline periods.	Other: post-resuscitation care; This study focused on the real-world, bundled implementation of successive ERC-ESICM guideline frameworks - rather than evaluating any single intervention (e.g., targeted temperature management, coronary angiography timing, or neuroprognostication alone). While most existing trials isolate one treatment component, this study captures the cumulative clinical effect of progressively refined, comprehensive post-resuscitation care bundles as delivered in routine ICU practice across three distinct guideline eras (2010, 2015, 2021) over 14 years within a single center. This longitudinal, within-institution design controls for center-level variability, allowing direct comparison of guideline-driven practice evolution and its impact on survival and neurological recovery. No experimental intervention is applied; the exposure of interest is the guideline framework active at the time of each patient's ICU admission.; Other Names: post-ROSC
Cohort B - 2015 ERC-ESICM Guidelines: Post-Cardiac Arrest Patients Managed per 2015 ERC Guidelines; Adult patients (≥18 years) admitted to the general ICU of S. Chiara Hospital, Trento, Italy, between January 2016 and March 2021, following successful resuscitation from in-hospital or out-of-hospital cardiac arrest of any etiology. This cohort was managed according to the 2015 ERC-ESICM Guidelines, which introduced a dedicated post-resuscitation care chapter and key updates including: targeted temperature management with an expanded target range (32-36°C), greater emphasis on urgent coronary angiography after cardiac arrest of presumed cardiac cause, and a multimodal neurological prognostication strategy incorporating clinical examination, electrophysiology, biomarkers, and brain imaging.	Other: post-resuscitation care; This study focused on the real-world, bundled implementation of successive ERC-ESICM guideline frameworks - rather than evaluating any single intervention (e.g., targeted temperature management, coronary angiography timing, or neuroprognostication alone). While most existing trials isolate one treatment component, this study captures the cumulative clinical effect of progressively refined, comprehensive post-resuscitation care bundles as delivered in routine ICU practice across three distinct guideline eras (2010, 2015, 2021) over 14 years within a single center. This longitudinal, within-institution design controls for center-level variability, allowing direct comparison of guideline-driven practice evolution and its impact on survival and neurological recovery. No experimental intervention is applied; the exposure of interest is the guideline framework active at the time of each patient's ICU admission.; Other Names: post-ROSC
Cohort C - 2021 ERC-ESICM Guidelines: Post-Cardiac Arrest Patients Managed per 2021 ERC Guidelines; Adult patients (≥18 years) admitted to the general ICU of S. Chiara Hospital, Trento, Italy, between April 2021 and April 2024, following successful resuscitation from in-hospital or out-of-hospital cardiac arrest of any etiology. This cohort was managed according to the 2021 ERC-ESICM Guidelines, which introduced further updates including: refined indications for coronary angiography, targeted temperature management with fever avoidance (>37.7°C) for at least 72 hours post-ROSC, updated hemodynamic targets (MAP ≥65 mmHg), stricter glucose control (140-180 mg/dL), preference for levetiracetam or sodium valproate for seizure management, expanded neuroprognosis algorithm, and enhanced guidance on ICU care, long-term follow-up, rehabilitation, and organ donation.	Other: post-resuscitation care; This study focused on the real-world, bundled implementation of successive ERC-ESICM guideline frameworks - rather than evaluating any single intervention (e.g., targeted temperature management, coronary angiography timing, or neuroprognostication alone). While most existing trials isolate one treatment component, this study captures the cumulative clinical effect of progressively refined, comprehensive post-resuscitation care bundles as delivered in routine ICU practice across three distinct guideline eras (2010, 2015, 2021) over 14 years within a single center. This longitudinal, within-institution design controls for center-level variability, allowing direct comparison of guideline-driven practice evolution and its impact on survival and neurological recovery. No experimental intervention is applied; the exposure of interest is the guideline framework active at the time of each patient's ICU admission.; Other Names: post-ROSC

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intensive Care Unit (ICU) Survival	To evaluate ICU survival for patients resuscitated from cardiac arrest.	From cardiac arrest date to ICU discharge or death, up to 90 days
Neurological Recovery at ICU Discharge	ICU Survival with Cerebral Performance Category (CPC) score of 1 or 2	From cardiac arrest date to ICU discharge or death, up to 90 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hospital discharge status.	To evaluate hospital survival for patients resuscitated from cardiac arrest.	From cardiac arrest date to hospital discharge or death, up to 180 days
Post-Resuscitation Care Guideline Implementation.	To evaluate guideline-recommended intervention adherence.	From cardiac arrest date to ICU discharge or death, up to 90 days

Collaborators and Investigators

• Sponsor: Azienda Sanitaria Universitaria Integrata del Trentino

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2025
• Primary Completion (Actual): October 31, 2025
• Study Completion (Actual): October 31, 2025

Study Registration Dates

• First Submitted: June 3, 2026
• First Submitted That Met QC Criteria: June 11, 2026
• First Posted (Actual): June 16, 2026

Study Record Updates

• Last Update Posted (Actual): June 16, 2026
• Last Update Submitted That Met QC Criteria: June 11, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: guidelines; cardiac arrest; post cardiac arrest syndrome; post resuscitation care
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Postoperative Complications; Pathologic Processes; Heart Diseases; Brain Injuries; Reperfusion Injury; Pathological Conditions, Signs and Symptoms; Post-Cardiac Arrest Syndrome; Heart Arrest
• Other Study ID Numbers: A1007

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Data protection regulations and institutional policies limit the dissemination of individual-level data. Therefore, only aggregated results will be made publicly available.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No