Retrospective Comparison of Upper and Lower Extremity Intraosseous Access During Out-of-Hospital Cardiac Arrest Resuscitation.

Intraosseous (IO) access is frequently utilized during the resuscitation of out-of-hospital cardiac arrest (OHCA) patients. Due to proximity to the heart and differential flow rates, the anatomical site of IO access may impact patient outcomes. Using a large dataset, we aimed to compare the outcomes of OHCA patients who received upper or lower extremity IO access during resuscitation. The ESO Data Collaborative public use research datasets were used for this retrospective study. All adult (≥18 years of age) OHCA patients with successful IO access in an upper or lower extremity were evaluated for inclusion. Patients were excluded if they had intravenous (IV) access prior to IO access, or if they had a Do Not Resuscitate order documented. Our primary outcome was return of spontaneous circulation (ROSC). Secondary outcomes included survival to discharge and survival to discharge to home. Mixed-effects multivariable logistic regression models adjusted for age, sex, etiology, witnessed status, pre-first responder cardiopulmonary resuscitation (CPR), initial electrocardiogram (ECG) rhythm, location [private/residential, public, or assisted living/institutional], and response time in addition to the primary airway management strategy (endotracheal intubation, supraglottic device, surgical airway, no advanced airway) were used to compare the outcomes of patients with upper extremity IO access to the outcomes of patients with lower extremity IO access. After application of exclusion criteria, 155,884 patients who received IO access during resuscitation remained (76% lower extremity, 24% upper extremity). Upper extremity IO access was associated with greater adjusted odds of ROSC (1.11 [1.08, 1.15]), and this finding was consistent across multiple patient subgroups. Secondary analyses suggested that upper extremity access was associated with increased survival to discharge (1.18 [1.00, 1.39]) and survival to discharge to home (1.23 [1.02, 1.48]) in comparison to lower extremity IO access. In this large prehospital dataset, upper extremity IO access was associated with a small increase in the odds of ROSC in comparison to lower extremity IO access. These data support the need for prospective investigation of the ideal IO access site during OHCA resuscitation. [ABSTRACT FROM AUTHOR]