Background: Effective management of out-of-hospital cardiac arrest (OHCA) relies upon adequate and timely establishment of a vascular access device (VAD) for the infusion of medications and fluids. However, VAD placement can be challenging in OHCA patients, even while receiving CPR, due to venous collapse. In this context, intraosseous (IO) cannulation may offer advantages over other VADs due to the non-collapsible marrow cavity. It is not known whether improved speed and reliability of IO access may also confer some clinical benefit to OHCA patients.
Methods: This is a retrospective cohort study of consecutive OHCA patients seen in two large, urban EDs in Detroit, Michigan. Data on presenting cardiac rhythm, time of ED arrival, time to establishment of useable VAD, medications given, return of spontaneous circulation (ROSC), and other details of the resuscitation were recorded. Standard statistical analysis was performed. Exclusion criteria included in-hospital cardiac arrest, pediatric patients, traumas, pregnancy, and subjects who did not receive a VAD in the ED.
Results: Nine hundred patient charts from a 2-year period (1 January 2014 to 31 December 2015) were reviewed and 363 subjects included. Of these, 55 (15.1%) received IO as their initial VAD; all remaining subjects received a peripheral intravenous line (PIV). Time to initial medication (TIM) was categorized as: 0-1 minute, 1-3 minutes, 3-5 minutes, and >5 minutes. Of the patients that achieved ROSC and were given IO medications, 66% were given medications within the first 3 minutes of ED arrival. A significant positive association was seen between IO TIM and increased rate of ROSC (p=0.0131), but no such association was seen with PIV TIM and ROSC (p=0.7277). A positive association was also noted between infusion of any medication through IO within 5 minutes of ED arrival and ROSC (p=0.0469). A total of 83 (22.9%) subjects realized sustained ROSC, with 72 (19.8%) surviving to hospital admission.
Conclusions: The use of IO cannulation for initial medication infusion was associated with a proportion of patients having achieved ROSC in this study, especially when the first medication was given within 5 minutes of ED arrival. This association was not seen with first medications given via PIV. Additional research is needed to determine how the choice of initial VAD may influence clinically relevant outcomes for OHCA patients.