No definitive answers as these are retrospectives analyses, but these articles raise questions that should have been answered before the movement toward "IO first" in cardiac arrest that many services have adopted.
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Intraosseous Vascular Access Is Associated With Lower Survival and Neurologic Recovery Among Patients With Out-of-Hospital Cardiac Arrest
Presented at the Canadian Association of Emergency Physicians congress, June 2017, Whistler, Canada.
Study objective
We seek to determine the effect of intraosseous over intravenous vascular access on outcomes after out-of-hospital cardiac arrest.
Methods
This secondary analysis of the Resuscitation Outcomes Consortium Prehospital Resuscitation Using an Impedance Valve and Early Versus Delayed (PRIMED) study included adult patients with nontraumatic out-of-hospital cardiac arrests treated during 2007 to 2009, excluding those with any unsuccessful attempt or more than one access site. The primary exposure was intraosseous versus intravenous vascular access. The primary outcome was favorable neurologic outcome on hospital discharge (modified Rankin Scale score ≤3). We determined the association between vascular access route and out-of-hospital cardiac arrest outcome with multivariable logistic regression, adjusting for age, sex, initial emergency medical services–recorded rhythm (shockable or nonshockable), witness status, bystander cardiopulmonary resuscitation, use of public automated external defibrillator, episode location (public or not), and time from call to paramedic scene arrival. We confirmed the results with multiple imputation, propensity score matching, and generalized estimating equations, with study enrolling region as a clustering variable.
Results
Of 13,155 included out-of-hospital cardiac arrests, 660 (5.0%) received intraosseous vascular access. In the intraosseous group, 10 of 660 patients (1.5%) had favorable neurologic outcome compared with 945 of 12,495 (7.6%) in the intravenous group. On multivariable regression, intraosseous access was associated with poorer out-of-hospital cardiac arrest survival (adjusted odds ratio 0.24; 95% confidence interval 0.12 to 0.46). Sensitivity analyses revealed similar results.
Conclusion
In adult out-of-hospital cardiac arrest patients, intraosseous vascular access was associated with poorer neurologic outcomes than intravenous access.
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The Effect of IV vs. IO Access in Prehospital Cardiac Arrest ROSC Rates
Colby Redfield, Stephen Suarez, Jessica Daniels, Cristina Sanchez, Heidi Siples, Kim Landry, Leon County EMS Category of Submission: Cardiac
Background: The prevailing standard of care in prehospital emergency medical services is that either intravenous (IV) or intraosseous (IO) are acceptable routes for obtaining vascular access and delivery of resuscitation medications and volume expanders in cardiac arrest patients. Our local EMS agency's current cardiac arrest protocol allows for either IV or IO access to be placed without preference. Objective: To evaluate the effectiveness of IV access versus IO access, in terms of Return of Spontaneous Circulation (ROSC), for patients suffering from cardiac arrest. Methods: Quality Improvement retrospective review project examining cardiac arrest data with a single ACLS EMS agency with average call volume of 37,000 calls annually. We examined a four year period from 2013 to 2016. Cardiac Arrest patients were identified from a Quality Assurance Database. Exclusion criteria included trauma arrest, pediatrics, pregnancy, and obvious signs of death. Method of vascular access was determined by reviewing the report and placed into an excel spreadsheet along with ROSC determination. Results: A total of 1,028 patient care reports were examined from January 1, 2013 to December 31, 2016. There were 230 patients where resuscitation was not initiated due to obvious signs of death. A total of 46 patients were excluded as trauma related cardiac arrests and 31 patients excluded due to age less than 18 years. A total of 721 patients remained after applying the exclusion criteria. A total of 361 cardiac arrest patients had an IV placed with a ROSC in 148 (41.1%). A total of 360 cardiac arrest patients had an IO placed with a ROSC in 80 (22.2%). IV use during cardiac arrest had improved ROSC when compared to IO use (p < 0.001). Conclusions: In this small retrospective review, there is a correlation between higher ROSC rates and IV access versus IO access. Limitations include small sample size, single EMS agency and retrospective nature of study. Future studies should further evaluate the effectiveness of IO vs IV access in cardiac arrest and other low perfusion states such as shock in a prospective manner.
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Resuscitation. 2017 Aug;117:91-96.
Intraosseous compared to intravenous drug resuscitation in out-of-hospital cardiac arrest.
Feinstein BA1, Stubbs BA2, Rea T3, Kudenchuk PJ4.
Author information
Abstract
AIMS:
Although the intraosseous (IO) route is increasingly used for vascular access in out-of-hospital cardiac arrest (OHCA), little is known about its comparative effectiveness relative to intravenous (IV) access. We evaluated clinical outcomes following OHCA comparing drug administration via IO versus IV routes.
METHODS:
This retrospective cohort study evaluated Emergency Medical Services (EMS)-treated adults with atraumatic OHCA in a large metropolitan EMS system between 9/1/2012-12/31/2014. Access was classified as IO or IV based on the route of first EMS drug administration. Study endpoints were survival to hospital discharge, return of spontaneous circulation (ROSC) and survival to hospital admission.
RESULTS:
Among 2164 adults with OHCA, 1800 met eligibility criteria, 1525 of whom were treated via IV and 275 principally via tibial-IO routes. Compared to IV, IO-treated patients were younger, more often women, had unwitnessed OHCA, a non-cardiac aetiology, and presented with non-shockable rhythms. IO versus IV-treated patients were less likely to survive to hospital discharge (14.9% vs 22.8%, p=0.003), achieve ROSC (43.6% vs 55.5%, p<0.001) or be hospitalized (38.5% vs 50.0% p<0.001). In multivariable adjusted analyses, IO treatment was not associated with survival to discharge (odds ratio (OR) (95% confidence interval) 0.81 (0.55, 1.21), p=0.31), but was associated with a lower likelihood of ROSC (OR=0.67 (0.50, 0.88), p=0.004) and survival to hospitalization (OR=0.68 (0.51, 0.91), p=0.009).
CONCLUSION:
Though not independently associated with survival to discharge, principally tibial IO versus IV treatment was associated with a lower likelihood of ROSC and hospitalization. How routes of vascular access influence clinical outcomes after OHCA merits additional study.
