Lactate in Cardiac Arrest

This will be a prospective observational study of all primary cardiac arrest patients with
prehospital (ROSC) in Alachua County, Florida. After Emergency Medical Services (EMS)
activation and arrival at scene of a cardiac arrest, paramedics and Emergency Medical
Technicians (EMTs) will provide standard Advanced Cardiac Life Support (ACLS) following 2010
guidelines. This may include chest compressions, early identification and shock of
ventricular fibrillation and ventricular tachycardia, obtaining intravenous (IV) or
intraosseous (IO) access, administration of IV or IO epinephrine, amiodarone, and pressors,
oxygenation and ventilation, and other treatments as indicated for reversible causes of
cardiac arrest. At time of IV or IO establishment a small blood sample will be obtained the
blood will be measured for blood lactate. EMS personnel will be specifically trained to not
to delay care or deviate from standard resuscitation protocols to obtain blood lactate
sample. Current local paramedic protocols for cardiac arrest and general medical management
include obtaining IV access and capillary blood draw and thus blood lactate measurement does
not require any additional invasive procedures or medical risk. As medical director of
Alachua County Fire Rescue (ACFR) as well as University of Florida faculty member, Dr.
Christine Van Dillen oversees paramedic training, protocol development, and quality
assurance in Alachua County, Florida. Dr Karl Huesgen is a faculty physician at the
University as well, and works closely with ACFR in these regards. These investigators meet
regularly with ACFR administration and provide mandatory paramedic and EMT education.
Incorporation of lactate measurement into standard cardiac arrest protocols will be
accomplished through the monthly administrative updates and monthly in-person training
sessions. Adherence to the investigative protocol will be monitored through the standard
quality assurance program in which all cardiac arrests are reviewed. Paramedics will have
the option of using either capillary or venous blood for lactate measurement. This
flexibility is important because cardiac arrests are often chaotic with substantial
variability between site of cardiac arrests, timing of return of spontaneous circulation
(e.g. if IV access obtained before cardiac rhythm restoration), patient anatomy (e.g. poor
venous access), provider resources (e.g. presence of additional rescue personnel), and other
factors. Ideally blood lactate measurement will occur at IV insertion, though it may be
measured later with equally valid results during fingerstick glucose measurement. Of note,
medical providers will be instructed to not perform any additional IV insertions or
fingersticks in order to obtain lactate measurements. Patients will be transported as
rapidly as possible to local hospitals.

Inclusion Criteria:

- All adult patients (≥ 18 years of age)

- Non-traumatic primary cardiac arrest

Exclusion Criteria:

- Patients with advanced directives precluding resuscitation,

- Traumatic cardiac arrest, and

- Irreversible signs of death (rigor mortis).