The association of intravenous vs. humeral-intraosseous vascular access with patient outcomes in adult out-of-hospital cardiac arrests.

AIM: While intravenous (IV) vascular access for out-of-hospital cardiac arrest (OHCA) resuscitation is standard, humeral-intraosseous (IO) access is commonly used, despite few supporting data. We investigated the association between IV vs. humeral-IO and outcomes. METHODS: We utilized BC Cardiac Arrest Registry data, including adult OHCA where the first-attempted intra-arrest vascular access route performed by advanced life support (ALS)-trained paramedics was IV or humeral-IO. We fit a propensity-score adjusted model with inverse probability treatment weighting to estimate the association between IV vs. humeral-IO routes and favorable neurological outcomes (CPC 1-2) and survival at hospital discharge. We repeated models within subgroups defined by initial cardiac rhythm. RESULTS: We included 2,112 cases; the first-attempted route was IV (n = 1,575) or humeral-IO (n = 537). Time intervals from ALS-paramedic on-scene arrival to vascular access (6.6 vs. 6.9 min) and epinephrine administration (9.0 vs. 9.3 min) were similar between IV and IO groups, respectively. Among IV and humeral-IO groups, 98 (6.2%) and 20 (3.7%) had favorable neurological outcomes. Compared to humeral-IO, an IV-first approach was associated with improved hospital-discharge favorable neurological outcomes (AOR 1.7; 95% CI 1.1-2.7) and survival (AOR 1.5; 95% CI 1.0-2.3). Among shockable rhythm cases, an IV-first approach was associated with improved favorable neurological outcomes (AOR 4.2; 95% CI 2.1-8.2), but not among non-shockable rhythm cases (AOR 0.73; 95% CI 0.39-1.4). CONCLUSION: An IV-first approach, compared to humeral-IO, for intra-arrest resuscitation was associated with an improved odds of favorable neurological outcomes and survival to hospital discharge. This association was seen among an initial shockable rhythm, but not non-shockable rhythm, subgroups.

A Local Sensitivity Analysis of the Trial of Continuous or Interrupted Chest Compressions during Cardiopulmonary Resuscitation: Is a Local Protocol Change Required?

Objective The "Trial of Continuous (CCC) or Interrupted Chest Compressions (ICC) during Cardiopulmonary Resuscitation (CPR)" compared two CPR strategies for out-of-hospital cardiac arrest (OHCA). Although results were neutral, there was suggestion of benefit for ICC. However, nearly 50% of study patients had a protocol violation; regional variations may have played a role in protocol adherence and outcomes. We analyzed our British Colombia (BC) cohort to decide whether a protocol change from CCC to ICC was justified. Methods This was a post-hoc analysis of BC-enrolled study patients. The primary between-group comparison was favorable neurological outcome (modified Rankin scale ≤ 3) using intention-to-treat. Secondary analyses compared those treated per-protocol (adjusted) and the top compliant clusters (unadjusted). We classified protocol violations using a structured algorithm. We used logistic regression and computed the difference in probabilities using the marginal standardization method with bootstrapping to calculate confidence intervals. Results There were 3769 patients included, with a median age of 69 years (IQR: 56-80). There were protocol violations in 3.2% of those in the CCC group and 27% of those in the ICC group. In patients randomized to CCC or ICC, 11.2% and 10.8% (risk difference 0.42%; 95% CI -1.58, 2.41) had favorable neurological outcomes, respectively. In the per-protocol and top compliant clusters comparisons, risk differences were 0.25% (95% CI -1.70, 2.25) and 2.95% (95% CI -0.68, 6.58). Conclusion Our comparisons suggest that CCC may be the preferred strategy in our region and is likely not resulting in worse outcomes. Based on the original study and our local analysis, we found no compelling reasons to change our local strategy from CCC to ICC.

Trends in care processes and survival following prehospital resuscitation improvement initiatives for out-of-hospital cardiac arrest in British Columbia, 2006-2016.

BACKGROUND: British Columbia (BC) Emergency Health Services implemented a strategy to improve outcomes for out-of-hospital cardiac arrest (OHCA), focusing on paramedic-led high-quality on-scene resuscitation. We measured changes in care metrics and survival trends. METHODS: This was a post-hoc study of prospectively identified consecutive non-traumatic ambulance-treated adult OHCAs from 2006 to 2016 within BC's four metropolitan areas. The primary outcome was survival to hospital discharge; we also described available favourable neurological outcomes (mRS ≤3). We tested the significance of year-by-year trends in baseline characteristics, and calculated risk-adjusted survival rates using multivariable Poisson regression. RESULTS: We included 15 145 patients. In univariate analyses there were significant increases in bystander CPR, chest compression fraction, advanced life support attendance, duration of resuscitation until advanced airway placement, duration of resuscitation until termination, and overall scene time. There was a significant decrease in initial shockable rhythms, bystander witnessed arrests, and transports initiated prior to ROSC. Survival and the proportion of survivors with favourable neurological outcomes increased significantly. In adjusted analyses, there was an improvement in return of spontaneous circulation (risk-adjusted rate 41% in 2006 to 51% in 2016; adjusted rate ratio per year 1.02, 95% CI 1.01-1.02, p < 0.01 for trend) and survival at hospital discharge (risk-adjusted rate 8.6% in 2006 to 16% in 2016; adjusted rate ratio per year 1.05, 95% CI 1.04-1.06, p < 0.01 for trend). CONCLUSION: From 2006 to 2016 BC's provincial ambulance system prioritized paramedic-led on-scene resuscitation, during which time there were significant improvements in patient outcomes. Our data may assist other systems, providing a model for prehospital resuscitation quality improvement.

Intraosseous Vascular Access Is Associated With Lower Survival and Neurologic Recovery Among Patients With Out-of-Hospital Cardiac Arrest.

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.