NEW YORK (Reuters Health) – Vascular access in patients experiencing out-of-hospital cardiac arrest is more reliably and rapidly obtained via needle insertion into the marrow cavity of the tibia, rather than into the humerus or a peripheral vein, according to a trial reported in the Annals of Emergency Medicine online August 19th.

“Results from this study may help stakeholders such as EMS medical directors choose the most appropriate site for first-attempt vascular access in out-of-hospital cardiac arrest,” the authors conclude.

Dr. Jonathan R. Studnek, with the Mecklenburg EMS Agency in Charlotte, North Carolina, and colleagues explain that intraosseous vascular access in the out-of-hospital setting is being used not only in children but also in adults, but the actual effectiveness of various needle insertion sites during cardiopulmonary resuscitation has not been determined.

The team studied this issue in a prospective randomized trial involving all non-traumatic out-of-hospital cardiac arrest patients in the Mecklenberg EMS catchment area over a 5-month period. The 182 patients were assigned to one of the three routes of vascular access: tibial intraosseous, humeral intraosseous or peripheral intravenous vascular access.

Paramedics with the agency were intensively trained in all three approaches, with the EZ-IO Power Driver (Vidacare, San Antonio, Texas) being used for intraosseous insertion. The study’s primary outcome was success in achieving a secure needle position with normal fluid flow at the first attempt.

Initial access was successful in 130 patients (71%), but the needle became dislodged in 17 (9%), so the first-attempt success rate was 62%, the investigators report.

Rates of success were 91% with tibial intraosseous access, 51% with humeral intraosseous access, and 43% with peripheral intravenous access, according to the report. Furthermore, respective times to initial success with the three approaches were 4.6, 7.0 and 5.8 minutes.

The median volume infused was highest with intravenous access (800 mL) compared with either intraosseous method (400 mL), the authors note. They think that difference “may have been confounded by an unequal distribution of transport times or patients pronounced dead on scene.”

In a capsule summary of the findings, the journal’s editor concludes: “For cardiac arrest or unconscious patients who require immediate vascular access but are unlikely to require large-volume fluid resuscitation, tibial intraosseous needle placement is advantageous.”

Reference:
Intraosseous Versus Intravenous Vascular Access During Out-of-Hospital Cardiac Arrest: A Randomized Controlled Trial
Ann Emerg Med 2011.