Out of Hospital Cardiac Arrest, Cardiac Arrest (CA), Endotracheal Intubation, Prehospital Airway Management in Patients With Cardiac Arrest
Conditions
Keywords
OHCA, endotracheal intubation, cardiopulmonary resuscitation, survival
Brief summary
This prospective observational study evaluated the association of prehospital endotracheal intubation (ETI) status with return of spontaneous circulation (ROSC), 28-day survival, and favorable neurological outcome in adult patients with out-of-hospital cardiac arrest (OHCA) transported to the emergency department (ED) by emergency medical services (EMS). In addition, the study investigated the causes of failed ETI attempts and examined other clinical factors associated with 28-day survival, including bystander cardiopulmonary resuscitation (CPR), initial cardiac rhythm, blood gas parameters, and prehospital airway management strategy.
Detailed description
This prospective observational cohort study was conducted in the ED of Haseki Training and Research Hospital between July 1, 2025, and December 31, 2025. Patients presenting to the ED with cardiac arrest during the study period were screened for eligibility. All patients received advanced cardiac life support (ACLS) in accordance with the 2025 European Resuscitation Council (ERC) guidelines. Data collected for each patient encompassed demographic characteristics (age, sex, and body mass index \[BMI\]) and comorbid conditions, including hypertension, diabetes mellitus, coronary artery disease, chronic kidney disease, and malignancy. Prehospital variables included witnessed arrest, bystander CPR, bystander automated external defibrillator (AED) use, no-flow duration, time from collapse to initiation of advanced life support (ALS), time from collapse to hospital arrival, hyperventilation, and initial cardiac rhythm (asystole/pulseless electrical activity \[PEA\] or ventricular fibrillation/pulseless ventricular tachycardia \[VF/pVT\]). Prehospital airway data were recorded in two ways: the airway device present on ED arrival (endotracheal tube in place, bag-valve-mask ventilation, or supraglottic airway) and prehospital ETI attempt status (successful ETI, failed ETI attempt, or no ETI attempt). ETI success and the reasons for failed ETI attempts were also recorded, as was the occurrence of prehospital ROSC. Upon arrival at the ED, body temperature, Glasgow Coma Scale (GCS) score (when assessable), and vasopressor use within the first hour were recorded. Arterial blood gas parameters, including pH, partial pressure of oxygen (PaO2), and partial pressure of carbon dioxide (PaCO2), were also documented. Clinical outcomes included ROSC, 28-day survival status, and neurological outcome. Patients were classified as survivors or non-survivors according to 28-day survival status. Demographic characteristics, comorbidities, prehospital time intervals, initial rhythm, blood gas parameters, and airway management variables were compared across these groups to identify factors associated with 28-day survival. For airway-specific analyses, patients were further categorized into three groups according to ETI status: successful ETI, failed ETI attempt, and no ETI attempt. Comparisons among these groups were performed to assess differences in demographic and clinical characteristics, prehospital resuscitation variables, ROSC, 28-day survival, and favorable neurological outcome according to ETI status.
Interventions
OTHERDemographics
The demographic profile of each patient was documented, including age and sex, to examine potential associations with survival and neurological outcomes.
OTHERComorbidities
Data on pre-existing chronic conditions were recorded, such as hypertension, diabetes mellitus, coronary artery disease, chronic kidney disease, and malignancy, in order to assess their potential impact on prognosis following OHCA.
Several prehospital factors were evaluated, including whether the cardiac arrest was witnessed, whether bystander cardiopulmonary resuscitation (CPR) was performed, the time from collapse to the initiation of CPR, and the time from collapse to EMS arrival. Additionally, the durations of no-flow (i.e., time without any CPR) and low-flow (i.e., time with CPR but without ROSC) were noted. The initial cardiac rhythm was categorized as ventricular fibrillation or pulseless ventricular tachycardia (VF/pVT), asystole, or pulseless electrical activity (PEA). Airway management methods used in the field were documented and classified as bag-valve-mask (BVM), supraglottic airway devices (SGAs), or endotracheal intubation (ETI). Other recorded interventions included prehospital defibrillation, administration of epinephrine (including total dosage), and use of mechanical chest compression devices. Whether ROSC was achieved prior to arrival at the emergency department was also noted.
DIAGNOSTIC_TESTArterial Blood Gas Parameters
Arterial blood gas parameters, including pH, partial pressure of oxygen (PaO2), and partial pressure of carbon dioxide (PaCO2), were also documented.
OTHER28-day survival
Survival status 28 days after advanced cardiac life support (ACLS) initiated following OHCA.
OTHERNeurological outcome
Neurological status assessed at day 28 using the Cerebral Performance Category (CPC) scale. Favorable neurological outcome was defined as CPC 1-2, and unfavorable neurological outcome was defined as CPC 3-5.
Sponsors
Haseki Training and Research Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥18 years * Out-of-hospital cardiac arrest (OHCA) * Transport to the emergency department by emergency medical services (EMS) * Initiated resuscitation/advanced cardiovascular life support (ACLS) by EMS * Enrollment period between July 1, 2025, and December 31, 2025
Exclusion criteria
* Age \<18 years * In-hospital cardiac arrest * Cardiac arrest due to major trauma, drowning, drug overdose, or known terminal illness * Tracheostomy present * Missing data on primary outcomes or admission laboratory parameters
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 28 day-survival rate | At 28 days after ACLS initiation following OHCA. | Survival status at day 28 after advanced cardiovascular life support (ACLS) initiated following out-of-hospital cardiac arrest (OHCA). Participants will be classified as survivors if alive on day 28 and as non-survivors if death occurs within 28 days. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Neurological Status at 28 Days | At 28 days after ACLS initiation following OHCA | Neurological status assessed 28 days after ACLS initiation following OHCA using the Cerebral Performance Category (CPC) scale. Favorable neurological outcome will be defined as CPC 1-2, and unfavorable neurological outcome as CPC 3-5. |
| Achievement of Return of Spontaneous Circulation (ROSC) During Resuscitation Following Out-of-Hospital Cardiac Arrest (OHCA). | Assessed within the first 20 minutes after emergency department admission. | ROSC was defined as the return of sustained spontaneous perfusing rhythm lasting at least 20 minutes without the need for external chest compressions. |
| Comparison of 28-Day Survival Rates Between Participants Who Underwent Prehospital Endotracheal Intubation and Those Who Did Not | At 28 days after ACLS initiation following OHCA | The investigators evaluate the impact of prehospital endotracheal intubation (ETI) on 28-day survival status. Survival was defined as being alive 28 days after the cardiac arrest event. Participants will be categorized into two groups based on whether or not they received ETI in the prehospital setting. |
Countries
Turkey (Türkiye)
Contacts
PRINCIPAL_INVESTIGATORAdem Az
Sultangazi Haseki Eğitim ve Araştırma Hastanesi, Başhekimlik
Outcome results
None listed