Safety and Adverse Events During Primary Care Paramedic Interfacility Transfer of Stable STEMI Patients.

OBJECTIVE: Current guidelines recommend that patients presenting with ST-elevation myocardial infarction (STEMI) to hospitals not capable of performing primary percutaneous coronary intervention (PCI) be transferred to a PCI-capable hospital if reperfusion can be accomplished within 120 min. Most STEMI patients are accompanied by an advanced care paramedic (ACP, equivalent to EMT-P), nurse, or physician who can manage complications should they arise. In our region, stable STEMI patients are transported by primary care paramedics (PCPs, similar scope of practice to advanced EMT) in cases where a nurse, physician, or ACP paramedic is not available. Our goal was to describe adverse events and need for advanced interventions among initially stable STEMI patients during interfacility transfer by PCPs. METHODS: We reviewed ambulance and hospital records of initially stable STEMI patients (as determined by first set of vital signs documented by paramedics) transferred to a PCI-capable hospital by PCPs between March 1, 2014, and December 31, 2019. We identified whether pre-determined adverse clinical events occurred during the transport as well as the potential need for advanced care interventions not within the PCP scope of practice. Adverse events upon arrival in the PCI lab were also identified. RESULTS: Of 346 STEMI patients transferred, 179 met inclusion criteria. The mean age of included patients was 61 years (SD 12.1) and 74.9% (134/179) were male. Median transport interval was 36 min (IQR 3.0). During transport, 47/179 (26.0%) patients experienced pre-defined adverse events; for 16/47 (34%), one or more adverse events was major. Three patients met criteria for ACP interventions. One patient suffered a cardiac arrest and was promptly resuscitated with defibrillation by the PCPs. CONCLUSIONS: We found PCP-interfacility transport of initially stable STEMI patients was safe and associated with a moderate proportion of adverse events, the majority of which did not require an advanced care intervention. These findings may help decision-making to avoid delays transferring stable patients to PCI-capable centers.

The impact of alternate defibrillation strategies on shock-refractory and recurrent ventricular fibrillation: A secondary analysis of the DOSE VF cluster randomized controlled trial.

BACKGROUND: The DOSE VF randomized controlled trial (RCT) employed a pragmatic definition of refractory ventricular fibrillation (VF after three successive shocks). However, it remains unclear whether the underlying rhythm during the first three shocks was shock-refractory or recurrent VF. OBJECTIVE: To explore the relationship between alternate defibrillation strategies employed during the DOSE VF RCT and the type of VF, either shock-refractory VF or recurrent VF, on patient outcomes. METHODS: We performed a secondary analysis of the DOSE VF RCT. We categorized cases as shock-refractory or recurrent VF based on pre-randomization shocks (shocks 1-3). We then analyzed all subsequent (post-randomization) shocks to assess the impact of standard, vector change (VC) or double sequential external defibrillation (DSED) shocks on clinical outcomes employing logistic regression adjusted for Utstein variables, antiarrhythmics, and epinephrine. RESULTS: We included 345 patients; 60 (17%) shock-refractory VF, and 285 (83%) recurrent VF. Patients in recurrent VF had greater survival than shock-refractory VF (OR: 2.76 95% CI [1.04, 7.27]). DSED was superior to standard defibrillation for survival overall, and for patients with shock-refractory VF (28.6% vs 0%, p = 0.041) but not for those in recurrent VF. DSED was superior to standard defibrillation for return of spontaneous circulation (ROSC) and neurologic survival for shock-refractory and recurrent VF. VC defibrillation was not superior for survival or ROSC overall, for shock-refractory, or recurrent VF groups, but was superior for VF termination across all groups. CONCLUSION: DSED appears to be the superior defibrillation strategy in the DOSE VF trial, irrespective of whether the preceding VF is shock-refractory or recurrent.

Association of coronary angiography with ST-elevation and no ST-elevation in patients with refractory ventricular fibrillation - A substudy of the DOuble SEquential External Defibrillation for Refractory Ventricular Fibrillation (DOSE-VF randomized control trial).

BACKGROUND: Refractory ventricular fibrillation or pulseless ventricular tachycardia (rVF/pVT) during out-of-hospital cardiac arrest (OHCA) is associated with poor survival. Double sequential defibrillation (DSED) and vector change (VC) improved survival for rVF/pVT in the DOSE-VF RCT. However, the role of angiography and percutaneous coronary intervention (angiography/PCI) during the trial is unknown. OBJECTIVES: To determine the incidence of ST-elevation (STE) and no ST-elevation (NO-STE) on post-arrest ECG and the use of angiography/PCI in patients with rVF/pVT during the DOSE-VF RCT. METHOD: Adults (≥18-years) with rVF/pVT OHCA randomized in the DOSE-VF RCT who survived to hospital admission were included. The primary analysis compared the proportion of angiography in STE and NO-STE. We performed regression modelling to examine association between STE, the interaction with defibrillation strategy, and survival to discharge controlling for known covariates. RESULTS: We included 151 patients, 74 (49%) with STE and 77 (51%) with NO-STE. The proportion of angiography was higher in the STE cohort than NO-STE (87.8% vs 44.2%, p < 0.001); similarly the proportion of PCI was also higher (75.7% vs 9.1%, p < 0.001). Survival to discharge was similar between STE and NO-STE (63.5% vs 51.9%, p = 0.15). Use of angiography/PCI did not differ between defibrillation strategies. Decreased age (OR 0.95, 95% CI 0.92-0.98; p = 0.001) and angiography (OR 9.33, 95% CI 3.60-26.94; p < 0.001) were predictors of survival; however, STE was not. CONCLUSION: We found high rates of angiography/PCI in patients with STE compared to NO-STE, however similar rates of survival. Angiography was an independent predictor of survival. Improved rates of survival employing DSED and VC were independent of angiography/PCI.

The impact of double sequential shock timing on outcomes during refractory out-of-hospital cardiac arrest.

BACKGROUND: Animal studies suggest the efficacy of double sequential external defibrillation (DSED) may depend on the interval between the two shocks, or "DSED interval". No human studies have examined this concept. OBJECTIVES: To determine the relationship between DSED interval and termination of ventricular fibrillation (VFT), return of spontaneous circulation (ROSC), survival to hospital discharge, and favourable neurological status (MRS ≤ 2) for patients in refractory VF. METHODS: We performed a retrospective review of adult (≥18 years) out-of-hospital cardiac arrest between January 2015 and May 2022 with refractory VF who received ≥1 DSED shock. DSED interval was divided into four pre-defined categories. We examined the association between DSED interval and patient outcomes using general estimated equation logistic regression or Fisher's exact test. RESULTS: Among 106 included patients, 303 DSED shocks were delivered (median 2, IQR 1-3). DSED intervals of 75-125 ms (OR 0.39, 95% CI 0.16-0.98), 125-500 ms (OR 0.36, 95% CI 0.16-0.82), and >500 ms (OR 0.27, 95% CI 0.11-0.63) were associated with lower probability of VF termination compared to <75 ms interval. DSED interval of >75 ms was associated with lower probability of ROSC compared to <75 ms interval (OR 0.37, 95% CI 0.14-0.98). No association was noted between DSED interval and survival to hospital discharge or neurologic outcome. CONCLUSIONS: Among patients in refractory VF a DSED interval of less than 75 ms was associated with improved rates of VF termination and ROSC. No association was noted between DSED interval and survival to hospital discharge or neurologic outcome.

The Impact of Out-of-Hospital Time and Prehospital Intubation on Return of Spontaneous Circulation following Resuscitative Thoracotomy in Traumatic Cardiac Arrest.

INTRODUCTION: Resuscitative thoracotomy (RT) is a critical procedure performed in certain trauma patients in extremis, with extremely low survival rates. Currently, there is a paucity of data pertaining to prehospital variables and their predictive role in survival outcomes in traumatic cardiac arrest (TCA) patients requiring RT. The aim of the study was to determine the impact of prehospital intubation and out-of-hospital time (OOHT) on return of spontaneous circulation (ROSC) and survival in TCA requiring RT. METHODS: This was a retrospective cohort study of trauma patients presenting to two level-1 trauma centers, St. Michael's Hospital and Sunnybrook Health Sciences Center, in Toronto, Canada (January 1, 2005-December 31, 2020). Our exposures of interest were any prehospital intubation attempt and OOHT. Primary and secondary outcome measures were ROSC post-RT and survival to hospital discharge, respectively, and data analysis was performed using univariate logistic regression. RESULTS: A total of 195 patients were included, of which 86% were male, and the mean age was 33 years. ROSC and survival to hospital discharge were achieved in 30% and 5% of patients, respectively. Of those who survived to discharge, 89% sustained penetrating trauma. There was no association between OOHT and ROSC (OR = 1.00, 95% CI 0.97-1.03) or survival (OR = 0.99, 95% CI 0.94-1.05). The odds of ROSC were lower in penetrating trauma in the presence of any prehospital intubation attempt (OR = 0.39, 95% CI 0.19-0.82, p = 0.01). ROSC was less likely among all patients with no prehospital signs of life (SOL) compared to those who had prehospital SOL (OR = 0.30, 95% CI 0.13-0.69, p < 0.01). CONCLUSIONS: There was a significant association between prehospital intubation and lower likelihoods of ROSC in the penetrating TCA population requiring RT, as well as with the absence of prehospital SOL in all patients. OOHT did not appear to significantly impact ROSC or survival.

Predefibrillation end-tidal CO2 and defibrillation success in out-of-hospital cardiac arrest: an observational cohort study.

BACKGROUND: Predefibrillation end-tidal CO2 (ETCO2) may predict defibrillation success and could guide defibrillation timing in ventricular fibrillation (VF) cardiac arrest. This relationship has only been studied using advanced airways. Our aim was to evaluate this relationship using both basic (bag-valve-mask (BVM)) and advanced airways (supraglottic airways and endotracheal tubes). METHODS: Prehospital patient records and defibrillator files were abstracted for patients with out-of-hospital cardiac arrest in Ontario, Canada, with initial VF cardiac rhythms between 1 January 2018, and 31 December 2019. Analyses assessed the relationship between each predefibrillation ETCO2 reading and defibrillation outcomes at the subsequent 2 min pulse check (ie, VF, asystole, pulseless electrical activity (PEA) or return of spontaneous circulation (ROSC)), accounting for airway types used during resuscitation. Multivariable logistic regression evaluated the association between the first documented predefibrillation ETCO2 and postshock VF termination or ROSC. RESULTS: Of 269 cases abstracted, 153 had predefibrillation ETCO2 measurements and were included in the study. Among these cases, 904 shocks were delivered and 44.4% (n=401) had predefibrillation ETCO2 measured. The first ETCO2 reading was more often from BVM (n=134) than advanced airways (n=19). ETCO2 readings were lower when measured through BVM versus advanced airways (30.5 mm Hg (4.06 kPa) (±14.4 mm Hg (1.92 kPa)) vs 42.1 mm Hg (5.61 kPa) (±22.5 mm Hg (3.00 kPa)), adjANOVA p<0.01). Of all shocks with ETCO2 reading (n=401), no difference in preshock ETCO2 was found for subsequent shocks that resulted in persistent VF (32.2 mm Hg (4.29 kPa) (±15.8 mm Hg (2.11 kPa))), PEA (32.8 mm Hg (4.37 kPa) (±17.1 mm Hg (2.30 kPa))), asystole (32.4 mm Hg (4.32 kPa) (±20.6 mm Hg (2.75 kPa))) or ROSC (32.5 mm Hg (4.33 kPa) (±15.3 mm Hg (2.04 kPa))), analysis of variance p=0.99. In the multivariate analysis using the initial predefibrillation ETCO2, there was no association with VF termination on the subsequent shock (adjusted OR (adjOR) 0.99, 95% CI 0.97 to 1.02, p=0.57) or ROSC (adjOR 1.00, 95% CI 0.97 to 1.03, p=0.94) when evaluated as a continuous or categorical variable. CONCLUSION: Predefibrillation ETCO2 measurement is not associated with VF termination or ROSC when basic and advanced airways are included in the analysis. The role of predefibrillation ETCO2 requires careful consideration of the type of airway used during resuscitation.

Defibrillation Strategies for Refractory Ventricular Fibrillation.

BACKGROUND: Despite advances in defibrillation technology, shock-refractory ventricular fibrillation remains common during out-of-hospital cardiac arrest. Double sequential external defibrillation (DSED; rapid sequential shocks from two defibrillators) and vector-change (VC) defibrillation (switching defibrillation pads to an anterior-posterior position) have been proposed as defibrillation strategies to improve outcomes in patients with refractory ventricular fibrillation. METHODS: We conducted a cluster-randomized trial with crossover among six Canadian paramedic services to evaluate DSED and VC defibrillation as compared with standard defibrillation in adult patients with refractory ventricular fibrillation during out-of-hospital cardiac arrest. Patients were treated with one of these three techniques according to the strategy that was randomly assigned to the paramedic service. The primary outcome was survival to hospital discharge. Secondary outcomes included termination of ventricular fibrillation, return of spontaneous circulation, and a good neurologic outcome, defined as a modified Rankin scale score of 2 or lower (indicating no symptoms to slight disability) at hospital discharge. RESULTS: A total of 405 patients were enrolled before the data and safety monitoring board stopped the trial because of the coronavirus disease 2019 pandemic. A total of 136 patients (33.6%) were assigned to receive standard defibrillation, 144 (35.6%) to receive VC defibrillation, and 125 (30.9%) to receive DSED. Survival to hospital discharge was more common in the DSED group than in the standard group (30.4% vs. 13.3%; relative risk, 2.21; 95% confidence interval [CI], 1.33 to 3.67) and more common in the VC group than in the standard group (21.7% vs. 13.3%; relative risk, 1.71; 95% CI, 1.01 to 2.88). DSED but not VC defibrillation was associated with a higher percentage of patients having a good neurologic outcome than standard defibrillation (relative risk, 2.21 [95% CI, 1.26 to 3.88] and 1.48 [95% CI, 0.81 to 2.71], respectively). CONCLUSIONS: Among patients with refractory ventricular fibrillation, survival to hospital discharge occurred more frequently among those who received DSED or VC defibrillation than among those who received standard defibrillation. (Funded by the Heart and Stroke Foundation of Canada; DOSE VF ClinicalTrials.gov number, NCT04080986.).

The association between end-tidal CO2 and return of spontaneous circulation after out-of-hospital cardiac arrest with pulseless electrical activity.

INTRODUCTION: End-tidal carbon dioxide (ETCO2) has been suggested to have prognostic implications during out-of-hospital cardiac arrest (OHCA). Our objective was to determine if the change in ETCO2 (delta ETCO2) during resuscitation was predictive of future return of spontaneous circulation (ROSC) in patients with pulseless electrical activity (PEA) arrests. METHODS: We performed a retrospective, observational study of adult (≥18 years of age) non-traumatic PEA OHCAs in two Canadian EMS systems over a two-year time frame beginning on January 1, 2018. Cases were excluded if there was a Do Not Resuscitate order (DNR), had no advanced airway, or had less than two ETCO2 recordings. We performed multivariable logistic regression to examine the association between ETCO2 measures and ROSC. Second, we examined the prognostic performance (sensitivity, specificity, NPV, PPV) for ETCO2 at specific thresholds for predicting ROSC. RESULTS: A total of 208 OHCA met inclusion criteria of which 67 (32%) obtained ROSC. After adjusting for pre-determined confounders, there was an association between delta ETCO2 and ROSC (odds ratio [OR] per 10 mmHg increase in ETCO2 of 1.74 (95% confidence interval [CI] 1.35 to 2.24); P value < 0.001). We also found significant associations between both initial ETCO2 and final ETCO2 with ROSC. CONCLUSION: Our analysis indicates that there is a positive linear relationship between delta ETCO2 and ROSC with values of delta ETCO2 > 20 mmHg being highly specific for ROSC in PEA patients. As such, patients with up-trending ETCO2 values should have resuscitation continued unless there is overwhelming clinical evidence to the contrary.

Gallstone ileus with an enterovaginal fistula: a rare complication of pelvic radiotherapy.

Gallstone ileus is a rare cause of small bowel obstruction. Chronic gallstone irritation can lead to the formation of a cholecystoduodenal fistula, with gallstone impaction typically in the terminal ileum. Rarely gallstones can become impacted in other structures such as the colon or can even erode through the bowel. We present an unusual case of a gallstone ileus which resulted in the formation of an enterovaginal fistula, secondary to previous pelvic radiotherapy. Our case highlights the importance of considering fistula formation as a late complication of radiotherapy and how this can alter expected features of other pathologies, such as a gallstone ileus.

DOuble SEquential External Defibrillation for Refractory Ventricular Fibrillation (DOSE VF): study protocol for a randomized controlled trial.

BACKGROUND: Despite high-quality cardiopulmonary resuscitation (CPR), early defibrillation, and antiarrhythmic medications, some patients remain in refractory ventricular fibrillation (VF) during out-of-hospital cardiac arrest. These patients have worse outcomes compared to patients who respond to initial treatment. Double sequential external defibrillation (DSED) and vector change (VC) defibrillation have been proposed as viable options for patients in refractory VF. However, the evidence supporting the use of novel defibrillation strategies is inconclusive. The objective of this study is to compare two novel therapeutic defibrillation strategies (DSED and VC) against standard defibrillation for patients with treatment refractory VF or pulseless ventricular tachycardia (pVT) during out-of-hospital cardiac arrest. RESEARCH QUESTION: Among adult (≥ 18 years) patients presenting in refractory VF or pulseless ventricular tachycardia (pVT) during out-of-hospital cardiac arrest, does DSED or VC defibrillation result in greater rates of survival to hospital discharge compared to standard defibrillation? METHODS: This will be a three-arm, cluster randomized trial with repeated crossover conducted in six regions of Ontario, Canada (Peel, Halton, Toronto, Simcoe, London, and Ottawa), over 3 years. All adult (≥ 18 years) patients presenting in refractory VF (defined as patients presenting in VF/pVT and remaining in VF/pVT after three consecutive standard defibrillation attempts during out-of-hospital cardiac arrest of presumed cardiac etiology will be treated by one of three strategies: (1) continued resuscitation using standard defibrillation, (2) resuscitation involving DSED, or (3) resuscitation involving VC (change of defibrillation pads from anterior-lateral to anterior-posterior pad position) defibrillation. The primary outcome will be survival to hospital discharge. Secondary outcomes will include return of spontaneous circulation (ROSC), VF termination after the first interventional shock, VF termination inclusive of all interventional shocks, and number of defibrillation attempts to obtain ROSC. We will also perform an a priori subgroup analysis comparing rates of survival for those who receive "early DSED," or first DSED shock is shock 4-6, to those who receive "late DSED," or first DSED shock is shock 7 or later. DISCUSSION: A well-designed randomized controlled trial employing a standardized approach to alternative defibrillation strategies early in the treatment of refractory VF is urgently required to determine if the treatments of DSED or VC defibrillation impact clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04080986 . Registered on 6 September 2019.

Field Implementation of Remote Ischemic Conditioning in ST-Segment-Elevation Myocardial Infarction: The FIRST Study.

BACKGROUND: Remote ischemic conditioning (RIC) is a noninvasive therapeutic strategy that uses brief cycles of blood pressure cuff inflation and deflation to protect the myocardium against ischemia-reperfusion injury. We sought to compare major adverse cardiovascular events (MACE) for patients who received RIC before PCI for ST-segment-elevation myocardial infarction (STEMI) compared with standard care. METHODS: We conducted a pre- and postimplementation study. In the preimplementation phase, STEMI patients were taken directly to the PCI lab. After implementation, STEMI patients received 4 cycles of RIC by paramedics or emergency department staff before PCI. The primary outcome was MACE at 90 days. Secondary outcomes included MACE at 30, 60, and 180 days. Inverse probability of treatment weighting using propensity scores estimated causal effects independent from baseline covariables. RESULTS: A total of 1667 (866 preimplementation, 801 postimplementation) patients were included. In the preimplementation phase, 13.4% had MACE at 90 days compared with 11.8% in the postimplementation phase (odds ratio [OR] 0.86, 95% CI 0.62-1.21). There were no significant differences in MACE at 30, 60, and 180 days. Patients presenting with cardiogenic shock or cardiac arrest before PCI were less likely to have MACE at 90 days (42.7% pre vs 27.8% post) if they received RIC before PCI (OR 0.52, 95% CI 0.27-0.98). CONCLUSIONS: A strategy of RIC before PCI for STEMI did not reduce 90-day MACE. Future research should explore the impact of RIC before PCI for longer-term clinical outcomes and for patients presenting with cardiogenic shock or cardiac arrest.

Double sequential external defibrillation for refractory ventricular fibrillation: The DOSE VF pilot randomized controlled trial.

OBJECTIVES: The primary objective was to determine the feasibility and safety of a cluster randomized controlled trial (RCT) with crossover comparing vector change defibrillation (VC) or double sequential external defibrillation (DSED) to standard defibrillation for patients experiencing refractory ventricular fibrillation (VF). Secondary objectives were to assess the rates of VF termination (VFT) and return of spontaneous circulation (ROSC). METHODS: We conducted a pilot cluster RCT with crossover in four Canadian paramedic services including all treated adult OHCA patients who presented in VF and received a minimum of three successive defibrillation attempts. Each EMS service was randomly assigned to provide standard defibrillation, VC or DSED. Agencies crossed over to an alternate defibrillation strategy after six months. RESULTS: 152 patients were enrolled. With respect to feasibility, 89.5% of cases received the defibrillation strategy they were randomly allocated to, and 93.1% of cases received a VC or DSED shock prior to the sixth defibrillation attempt. There were no safety concerns reported. In the standard group, 66.6% of cases resulted in VFT, compared to 82.0% in VC and 76.3% in the DSED group. ROSC was achieved in 25.0%, 39.3% and 40.0% of standard, VC and DSED groups, respectively. CONCLUSIONS: Our findings suggest the DOSE-VF protocol is feasible and safe. Rates of VFT and ROSC were higher in the VC and DSED than standard defibrillation. The results of this pilot trial will allow us to inform a multicenter cluster RCT with crossover to determine if alternate defibrillation strategies for refractory VF may impact clinical outcomes.

The impact of double sequential external defibrillation on termination of refractory ventricular fibrillation during out-of-hospital cardiac arrest.

BACKGROUND: Despite significant advances in resuscitation efforts, there are some patients who remain in ventricular fibrillation (VF) after multiple shocks during out-of-hospital cardiac arrest (OHCA). Double sequential external defibrillation (DSED) has been proposed as a treatment option for patients in refractory VF. OBJECTIVE: We sought to explore the relationship between type of defibrillation (standard vs DSED), the number of defibrillation attempts provided and the outcomes of VF termination and return of spontaneous circulation (ROSC) for patients presenting in refractory VF. METHODS: We performed a retrospective review of all treated adult OHCA who presented in VF and received a minimum of three successive standard defibrillations over a three-year period beginning on January 1, 2015 in four Canadian EMS agencies. Using ambulance call reports and defibrillator files, we compared rates of VF termination (defined as the absence of VF at the rhythm check following defibrillation and two minutes of CPR) and VF termination to ROSC for patients who received standard defibrillation and those who received DSED (after on-line medical consultation). Cases with public access defibrillation, those with do not resuscitate orders, and those who presented in VF but terminated VF prior to three shocks were excluded. RESULTS: Of the 252 patients included, 201 (79.8%) received standard defibrillation only and 51 (20.2%) received at least one DSED. Overall, VF termination was similar between standard defibrillation and DSED (78.1% vs. 76.5%; RR: 1.0; 95% CI: 0.8-1.2). In our shock-based analysis, when early defibrillation attempts were considered (defibrillation attempt 4-8), VF termination was higher for those receiving DSED compared to standard defibrillation (29.4% vs. 17.5%; RR: 1.7; 95% CI: 1.1-2.6). Overall, VF termination to ROSC was similar between standard defibrillation and DSED (21.4% vs. 17.6%; RR: 0.8; 95% CI: 0.4-1.6). Additionally, when early defibrillation attempts were considered (defibrillation attempt 4-8), ROSC was higher for those receiving DSED compared to standard defibrillation (15.7% vs. 5.4%; RR: 2.9; 95% CI: 1.4-5.9). When late defibrillation attempts were considered (defibrillation attempt 9-17), VF termination was higher for those receiving DSED compared to standard defibrillation (31.2% vs. 17.1%; RR: 1.8; 95% CI: 1.1-3.0), but ROSC was rare regardless of defibrillation strategy. When DSED terminated VF into ROSC, it did so with a single DSED attempt in 66.7% of cases. CONCLUSIONS: Our observational findings suggest that while overall VF termination and ROSC are similar between standard defibrillation and DSED, earlier DSED may be associated with improved rates of VF termination and ROSC compared to standard defibrillation for refractory VF. A randomized controlled trial is required to assess the impact of early application of DSED on patient-important outcomes.

Serious gaming: A tool to educate health care providers about domestic violence.

Due to many adverse health effects, victims of domestic violence are frequently seen in the health care system. Yet, health care providers may lack the training to assist them. Online curricula can be an effective instructional tool. Our competency-based, serious video game, Responding to Domestic Violence in Clinical Settings, was designed to address health care providers' knowledge gaps through 17 modules, each a half hour in length. Nearly 9,000 participants completed at least one module; nursing students completed the most modules, approximately five hours of instruction. This serious video game-based curriculum is useful in helping health providers and students learn about Domestic Violence.

Labeling Bacterial Flagella with Fluorescent Dyes.

We describe labeling of bacteria with amino-specific or sulfhydryl-specific Alexa Fluor dyes, methods that allow visualization of flagellar filaments, even in swimming cells. Bacterial flagellar filaments are long (~10 µm), but of small diameter (~20 nm), and their rotation rates are high (>100 Hz), so visualization is difficult. Dark-field microscopy works well with isolated filaments, but visualization in situ is hampered by light scattered from cell bodies, which obscures short filaments or the proximal ends of long filaments. Differential interference contrast microscopy also works, but is technically difficult and suffers from a narrow depth of field and low image contrast; background subtraction and contrast enhancement are necessary. If filaments are fluorescent, they can be imaged in their entirety using standard fluorescence microscopes. For imaging in vivo, blurring can be prevented by strobing the light source or by using a camera with a fast shutter. The former method is preferred, since it minimizes bleaching.

Evaluation of a primary care paramedic STEMI bypass guideline.

OBJECTIVE: Limited evidence supports primary care paramedic (PCP) direct transport of ST-segment elevation myocardial infarction (STEMI) patients for percutaneous coronary intervention (PCI). The goal of this study was to evaluate an urban-based PCP STEMI bypass guideline. METHODS: We reviewed consecutive Toronto Paramedic Services call reports between April 7, 2015, and May 31, 2016, regarding STEMI patients identified by PCPs. The primary outcome was patient assignment (stable versus unstable) according to guideline criteria. Secondary outcomes were the proportion of PCP-transported patients who had an indication for an advanced care intervention (ACI) or who received an ACI when PCPs rendezvoused with an advanced care paramedic (ACP). Lastly, we reviewed prehospital outcomes of cardiac arrest patients and calculated the difference in transport intervals between direct PCP bypass and a PCI-centre and predicted transport interval to the closest emergency department (ED). RESULTS: Of 361 patients, 232 were PCP transports and 129 were ACP-rendezvous transports. There was a significant difference in the distribution of stable and unstable patients between PCPs and ACPs (p<0.001). For PCP patients, 21/232 (9.1%) had indications for an ACI, whereas 34/129 (26.4%) ACP patients received an ACI. Eleven patients experienced cardiac arrest; 10 were successfully resuscitated (5 of these by PCPs). The median difference between direct PCP bypass and a PCI-centre versus transport to the closest ED was 5.53 minutes (IQR=6.71). CONCLUSIONS: We found a significant difference in the distribution of stable and unstable patients and fewer patients with indications for an ACI in PCP patients. This PCP STEMI bypass guideline appears feasible.

Applying Kane's validity framework to a simulation based assessment of clinical competence.

Assessment of clinical competence is complex and inference based. Trustworthy and defensible assessment processes must have favourable evidence of validity, particularly where decisions are considered high stakes. We aimed to organize, collect and interpret validity evidence for a high stakes simulation based assessment strategy for certifying paramedics, using Kane's validity framework, which some report as challenging to implement. We describe our experience using the framework, identifying challenges, decisions points, interpretations and lessons learned. We considered data related to four inferences (scoring, generalization, extrapolation, implications) occurring during assessment and treated validity as a series of assumptions we must evaluate, resulting in several hypotheses and proposed analyses. We then interpreted our findings across the four inferences, judging if the evidence supported or refuted our proposed uses of the assessment data. Data evaluating "Scoring" included: (a) desirable tool characteristics, with acceptable inter-item correlations (b) strong item-total correlations (c) low error variance for items and raters, and (d) strong inter-rater reliability. Data evaluating "Generalizability" included: (a) a robust sampling strategy capturing the majority of relevant medical directives, skills and national competencies, and good overall and inter-station reliability. Data evaluating "Extrapolation" included: low correlations between assessment scores by dimension and clinical errors in practice. Data evaluating "Implications" included low error rates in practice. Interpreting our findings according to Kane's framework, we suggest the evidence for scoring, generalization and implications supports use of our simulation-based paramedic assessment strategy as a certifying exam; however, the extrapolation evidence was weak, suggesting exam scores did not predict clinical error rates. Our analysis represents a worked example others can follow when using Kane's validity framework to evaluate, and iteratively develop and refine assessment strategies.

A comparison of intimate partner and other sexual assault survivors' use of different types of specialized hospital-based violence services.

BACKGROUND: Little is known about the health service utilization of women sexually assaulted by their intimate partners, as compared with those sexually assaulted by other perpetrators. To address this gap, we describe the use of acute care services post-victimization, as well as a broad range of survivor and assault characteristics, across women assaulted by current or former intimate partners, other known assailants, and strangers. METHODS: Information was gathered from individuals presenting to 30 hospital-based sexual assault and domestic violence treatment centres using a standardized data collection form. We examined the data from 619 women 16 years of age or older who were sexually assaulted by one assailant. RESULTS: Women sexually assaulted by a current or former intimate partner were less likely than those assaulted by another known assailant or a stranger to have been administered emergency contraception (p < 0.001) or prophylaxis for sexually transmitted infections (p < 0.001), and counselled for potential use of HIV post-exposure prophylaxis (p < 0.001). However, these women were more likely than those in the other two groups to have had their injuries documented with photographs (p < 0.001), have undergone a risk assessment (p = 0.008), and/or have engaged in safety planning (p < 0.001). CONCLUSIONS: Women sexually assaulted by current or former intimate partners utilized services offered by sexual assault and domestic violence treatment centres differently than those assaulted by other known assailants and strangers. This may reflect their different health, forensic, and social needs, as well as the importance of offering care tailored to their particular circumstances.