Aim:

The aim of this prospective observational study is to determine the prevalence of bacteremia in out-of-hospital cardiac arrest patients (OHCA) presenting to the emergency department at AUBMC.

Objectives:

1.      To determine the prevalence of OHCA patients that are bacteremic upon presentation to the ED.

2.      To assess the characteristics associated with bacteremia among OHCA patients and compared to the non-bacteremic OHCA group.

3.      To describe the patient characteristics, the early post-arrest hospital courses, hospital mortality and outcomes of the bacteremic OHCA compared to the non-bacteremic OHCA group.

Study design

A prospective observational study of out of hospital cardiac arrest (OHCA) adult patients presenting to the ED at AUBMC between October 2015 and August 2019.

 Outcomes

The primary outcome is to determine the prevalence of OHCA patients that are bacteremic.

The secondary outcome is to compare mortality between bacteremic and non-bacteremic OHCA patients.

-          Out-of hospital cardiac arrest patients older than 18 years of age.

Patients who underwent resuscitation in the ED (received Advanced Cardiac Life Support (ACLS) and medical care in the ED) as a result of their OHCA.

All patients included in the study will receive the same standard of care for usually provided for all OHCA victims that present to the ED.  Once enrolled in the study, the research assistant will verify that the medical team ordered the panel of tests that is usually ordered on all OHCA survivors for all patients included in the study.  The process of drawing blood for analysis and culture will be performed during active resuscitation by an AUBMC registered nurse/phlebotomist who is not part of the resuscitation team to ensure that he/she will not interfere or cause delays in the resuscitation. The ABG will be drawn by a respiratory therapist.

The study will aim to collect the following information from OHCA patients: the vital signs upon presentation to ED; OHCA symptoms (according to Utstein classification); past medical history, regular cardiac arrest blood work (CBC, BUN, Creatinine, Electrolytes, Bilirubin, Troponin, Lactate, Arterial Blood Gas), two blood cultures, urine analysis and urine cultures, outcome of any special procedures; use of vasopressors/inotropes/antibiotics/steroids; patient disposition; the presence or absence of bacteremia and mortality at 72h and 28days.

In order to determine the presence or absence of bacteremia two sets of aerobic and anaerobic blood cultures (each with 10 ml of blood per bottle) will be collected from venous or arterial access (as per standard clinical care). 

Patients will be classified into the bacteremic OHCA group after confirmation of bacterial growth within five days in one blood culture tube with non-skin flora pathogens or in a minimum of two blood culture bottles with skin flora pathogens. Skin-indigenous bacteria in only one of two blood samples will be regarded as contamination and categorized as non-bacteremic OHCA.

Patients will be followed throughout their hospital stay. The main outcomes that will be examined will include the following: prevalence of bacteremia, survival rate to hospital discharge, neurologic outcome at hospital discharge and the 28 days mortality. The research assistant will call the patient after 28d with a follow up phone call to determine 28 days mortality.

All data will be collected from patient charts that can be accessed through the electronic health record system (EHR). The results of the Laboratory analyses will be accessed via the patient health information system (HIS).