Post Arrest Research Articles

SAT-595 Ventricular Fibrillation as a Manifestation of Hyperthyroidism

Background: Thyrotoxicosis is a known cause of atrial arrhythmias however, ventricular arrhythmias in this setting are rare. We report a case of ventricular fibrillation (VF) in a patient with Graves hyperthyroidism in the absence of coronary disease. Clinical Case: A 55-year old woman with hypertension and a self-reported thyroid nodule presented with a two week history of general malaise, palpations, diarrhea and muscle aches. Her mother had a goiter and paternal aunt required a thyroidectomy. Both her father and paternal uncle died at age 58 and 60 respectively of myocardial infarction. She was tachycardic to 125 beats per minute (bpm) and had a firm goiter with no bruit and normal reflexes. TSH was <0.01, free T4 > 6.99 ng/dL (n= 0.7-2.19 ng/dL), total T3 > 7.81 ng/mL (n=0.97 -1.7 ng/mL), thyroid stimulating immunoglobulin 516 % (n= <140%), and thyroid binding inhibitory immunoglobulin was 82.5% (n=<16%). Treatment with dexamethasone, methimazole, and propranolol was initiated. Homogenous increased uptake was seen in the thyroid gland on nuclear medicine scan. On day two of admission, her total T3 remained > 7.81 ng/mL despite therapy but her heart rate was better controlled at 100 bpm. However, that night she suffered a 40- minute cardiac arrest from VF. Spontaneous circulation was restored after multiple shocks, amiodarone and lidocaine, and then temporary pacing for bradycardia. She received a total of 440mg of propranolol and 40mg of methimazole prior to cardiac arrest. Serum potassium was normal pre arrest but rose to 6.9 mmol/L (n=3.5-5.1 mmol/L) after. Given the bradycardia, glucagon was given for possible beta blocker toxicity although this was thought to be unlikely as telemetry did not reveal pre-arrest bradycardia. There was no evidence of a coronary event since admission troponin was negative and post arrest troponin was only mild elevated with a flat trend. No wall motion abnormality was see on echocardiogram and ventricular function was preserved. Cardiac catheterization was deferred due to declining renal function. Subsequent myocardial perfusion imaging displayed only an apical cap artifact and coronary CT angiogram was free from atherosclerosis. She had no further arrhythmias. An implantable cardioverter defibrillator was placed prior to discharge for secondary prevention of ventricular arrhythmias. Conclusion: VF in the absence of underlying coronary disease or heart failure is rare in thyrotoxicosis. Thyroid hormone induced coronary vasospasm and activation of regionally varied beta-adrenergic receptors are proposed mechanisms for VF. Further, some individuals may have genetic predisposition to this in the setting of hyperthyroidism. This case highlights the urgency of achieving a euthyroid state and closely monitoring individuals with a family or personal history of ventricular arrhythmias or sudden cardiac death.

Survival of in-hospital cardiac arrest in men and women in a large Swedish cohort

BackgroundCardiac arrest is more common in men than women and a few studies have shown inferior 30-day survival for men than for women. The difference might relate to patient characteristics, intra arrest factors or post arrest care.AimTo assess differences in 30-day survival between men and women after an in-hospital cardiac arrest (IHCA).Material and methodsAll patients ≥18 years suffering an IHCA at Karolinska University Hospital between 2007 and 2017 were included. Data regarding the IHCA, patient characteristics, Charlson co-morbidity index (CCI) and 30-day survival were obtained from electronic patient records. Differences in survival between men and women were assessed with adjusted logistic regression models and presented as Odds Ratios with 95% Confidence Intervals (OR, 95% CI). Adjustments included age, CCI, place of cardiac arrest, first rhythm, ECG-surveillance and witnessed or not.ResultsIn all, 1639 patients suffered an IHCA, of whom 650 (40%) were women and 193 (30%) of them survived to 30 days compared to 28% of the men. No differences were found in the studied patient characteristics, intra arrest factors or post-ROSC treatments. Men had similar survival as women (crude OR 0.93 95% CI 0.74–1.15 and adjusted OR 0.77 95% CI 0.58–1.03 respectively).ConclusionThis cohort study illuminates an almost equal distribution in characteristics and treatment as well as outcome, 30-day survival after IHCA between men and women. However, our study confirms previous findings of disadvantageous prerequisites among women, but also indicates that preceeding vital signs differ which might indicate residual confounding.

Markers of cardiogenic shock predict persistent acute kidney injury after out of hospital cardiac arrest

ObjectiveIschemia and reperfusion injury (IRI) in cardiac arrest patients after return to spontaneous circulation causes dysfunctions in multiple organs. Kidney injury is generally transient but in some patients persists and contributes both to mortality and increased resource utilisation. Ongoing shock may compound renal injury from IRI, resulting in persistent dysfunction. We tested whether cardiac dysfunction was associated with the development of persistent acute kidney injury (PAKI) in the first 72 h after cardiac arrest. MethodsWe performed an observational retrospective study from January 2013 to April 2017. We included consecutive patients treated after out-of-hospital cardiac arrest at a single academic medical center with renal function measured and immediately and for 48 h post arrest. We also recorded each patient's pre arrest baseline creatinine, demographic and clinical characteristics. Our primary outcome of interest was PAKI, defined as acute kidney injury (AKI) on at least 2 measurements 24 h apart. We compared demographics and outcomes between patients with PAKI and those without, and used logistic regression to identify independent predictors of PAKI. ResultsOf 98 consecutive patients, we excluded 24 for missing data. AKI was present in 75% of subjects on arrival. PAKI developed in 35% of patients. PAKI patients had a longer hospital length of stay (median 21 vs 11 days) and lower hospital survival (47% vs 71%).Serum lactate levels, dosage of adrenaline during resuscitation and days of dobutamine infusion strongly predicted PAKI. ConclusionsAmong patient who survive cardiac arrest, acute AKI is common and PAKI occurs in more than one third. PAKI is associated both with survival and with length of stay at the hospital. High doses of adrenaline, high serial serum lactate levels, and dose of dobutamine predict PAKI. Evaluation of the trajectory of renal function over the first few days after resuscitation can provide prognostic information about patient recovery.

Abstract 216: Renal Failure After Cardiac Arrest and the role of Targeted Temperature Management

Introduction: While Acute Kidney Injury (AKI) is a common complication of cardiac arrest (CA), the incidence of AKI and Chronic Kidney Disease (CKD) following resuscitation are not well studied. Further, the association of Targeted Temperature Management (TTM) with AKI and CKD incidence has not been extensively studied. Aim: We compared the incidence of post-arrest AKI and CKD among patients who received TTM and those who did not receive TTM. Methods: In this retrospective cohort study, we studied adult patients following resuscitation from out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA). Serum creatinine (Cr) data for post-arrest patients were extracted from the electronic medical record. Baseline serum Cr was defined as the most recent pre-arrest Cr value or the lowest Cr value within 6 hrs of arrest. Using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria, AKI was defined as an increase in Cr by &gt; 0.3 mg/dL within 48 hrs or an increase in serum Cr by 1.5x the baseline value within a one-week period. CKD was defined as a GFR of &lt; 60 mL/min per 1.73 m 2 3 months post-arrest. Results: From 1/2005 to 12/2017, 1099 patients had serial post-arrest creatinine values available. Median age at arrest was 63 (IQR 25), 58% were male, survival to discharge was 20%, with a 17 % favorable CPC score of 1 or 2. Of these, 240 patients had documented TTM status (89 received TTM and 151 did not). Of the patients who received TTM, 31% developed AKI compared to 40 % who did not receive TTM (P=NS). The incidence of CKD was 56% in the TTM group and 45% in the non-TTM group. McNemar’s test for CKD at baseline and at 3 months post-arrest showed a significant increase in the incidence of CKD post arrest (45% vs. 49%, p = 0.031). Conclusions: Post cardiac arrest, AKI and CKD are common complications. The use of TTM was not associated with the incidence of AKI or CKD. Further research is needed to study factors that affect AKI and CKD in CA.

Highly malignant routine EEG predicts poor prognosis after cardiac arrest in the Target Temperature Management trial

IntroductionRoutine EEG is widely used and accessible for post arrest neuroprognostication. Recent studies, using standardised EEG terminology, have proposed highly malignant EEG patterns with promising predictive ability. ObjectivesTo validate the performance of standardised routine EEG patterns to predict neurological outcome after cardiac arrest. MethodsIn the prospective multicenter Target Temperature Management trial, comatose cardiac arrest patients were randomised to different temperature levels (950 patients, 36 sites). According to the prospective protocol a routine EEG was performed in patients who remained comatose after the 36 h temperature control intervention. EEGs were retrospectively reviewed blinded to outcome using the standardised American Clinical Neurophysiology Society terminology. Highly malignant, malignant and benign EEG patterns were correlated to poor and good outcome, defined by best achieved Cerebral Performance Category up to 180 days. ResultsAt 20 sites 207 patients had a routine EEG performed at median 76 h after cardiac arrest. Highly malignant patterns (suppression or burst-suppression with or without discharges) had a high specificity for poor outcome (98%, CI 92–100), but with limited sensitivity (31%, CI 24–39). Our false positive patient had a burst-suppression pattern during ongoing sedation. A benign EEG, i.e. continuous normal-voltage background without malignant features, identified patients with good outcome with 77% (CI 66–86) sensitivity and 80% (CI 73–86) specificity. ConclusionHighly malignant routine EEG after targeted temperature management is a strong predictor of poor outcome. A benign EEG is an important indicator of a good outcome for patients remaining in coma.

Shock subtypes by left ventricular ejection fraction following out-of-hospital cardiac arrest

BackgroundPost-resuscitation hemodynamic instability following out-of-hospital cardiac arrest (OHCA) may occur from myocardial dysfunction underlying cardiogenic shock and/or inflammation-mediated distributive shock. Distinguishing the predominant shock subtype with widely available clinical metrics may have prognostic and therapeutic value.MethodsA two-hospital cohort was assembled of patients in shock following OHCA. Left ventricular ejection fraction (LVEF) was assessed via echocardiography or cardiac ventriculography within 1 day post arrest and used to delineate shock physiology. The study evaluated whether higher LVEF, indicating distributive-predominant shock physiology, was associated with neurocognitive outcome (primary endpoint), survival, and duration of multiple organ failures. The study also investigated whether volume resuscitation exhibited a subtype-specific association with outcome.ResultsOf 162 patients with post-resuscitation shock, 48% had normal LVEF (> 40%), consistent with distributive shock physiology. Higher LVEF was associated with less favorable neurocognitive outcome (OR 0.74, 95% CI 0.58–0.94 per 10% increase in LVEF; p = 0.01). Higher LVEF also was associated with worse survival (OR 0.81, 95% CI 0.67–0.97; p = 0.02) and fewer organ failure-free days (β = – 0.67, 95% CI – 1.28 to − 0.06; p = 0.03). Only 51% of patients received a volume challenge of at least 30 ml/kg body weight in the first 6 h post arrest, and the volume received did not differ by LVEF. Greater volume resuscitation in the first 6 h post arrest was associated with favorable neurocognitive outcome (OR 1.59, 95% CI 0.99–2.55 per liter; p = 0.03) and survival (OR 1.44, 95% CI 1.02–2.04; p = 0.02) among patients with normal LVEF but not low LVEF.ConclusionsIn post-resuscitation shock, higher LVEF—indicating distributive shock physiology—was associated with less favorable neurocognitive outcome, fewer days without organ failure, and higher mortality. Greater early volume resuscitation was associated with more favorable neurocognitive outcome and survival in patients with this shock subtype. Additional studies with repeated measures of complementary hemodynamic parameters are warranted to validate the clinical utility for subtyping post-resuscitation shock.

Comparison of three haemodynamic monitoring methods in comatose post cardiac arrest patients*

Objectives. Haemodynamic monitoring during post arrest care is important to optimise treatment. We compared stroke volume measured by minimally-invasive monitoring devices with or without thermodilution calibration, and transthoracic echocardiography (TTE), and hypothesised that thermodilution calibration would give stroke volume index (SVI) more in agreement with TTE during targeted temperature management (TTM). Design. Comatose out-of-hospital cardiac arrest survivors receiving TTM (33 °C for 24 hrs) underwent haemodynamic monitoring with arterial pulse contour analyses with (PiCCO2®) and without (FloTrac®/Vigileo® monitor®) transpulmonary thermodilution calibration. Haemodynamic parameters were collected simultaneously every fourth hour during TTM (hypothermia) and (normothermia). SVI was measured with TTE during hypothermia and normothermia. Bland-Altman analyses were used for determination of SVI bias (±1SD). Results. Twenty-six patients were included, of whom 77% had initial shockable rhythm and 52% discharged with good outcome. SVI (bias ±2SD) between PiCCO (after thermodilution calibration) vs FloTrac/Vigileo, TTE vs FloTrac/Vigileo and TTE vs PiCCO were 1.4 (±25.8), −1.9 (±19.8), 0.06 (±18.5) ml/m2 during hypothermia and 9.7 (±23.9), 1.0 (±17.4), −7.2 (±12.8) ml/m2 during normothermia. Continuous SVI measurements between PiCCO and FloTrac/Vigileo during hypothermia at reduced SVI (<35 ml/m2) revealed low bias and relatively narrow limits of agreement (0.5 ± 10.2 ml/m2). Conclusion. We found low bias, but relatively wide limits of agreement in SV with PiCCO, FloTrac/Vigileo and TTE during TTM treatment. The methods are not interchangeable. Precision was not improved by transpulmonary thermodilution calibration during hypothermia.

Emergency Medicine Myths: Epinephrine in Cardiac Arrest

BackgroundSudden cardiac arrest accounts for approximately 15% of deaths in developed nations, with poor survival rate. The American Heart Association states that epinephrine is reasonable for patients with cardiac arrest, though the literature behind its use is not strong. ObjectiveTo review the evidence behind epinephrine for cardiac arrest. DiscussionSudden cardiac arrest causes over 450,000 deaths annually in the United States. The American Heart Association recommends epinephrine may be reasonable in patients with cardiac arrest, as part of Advanced Cardiac Life Support. This recommendation is partly based on studies conducted on dogs in the 1960s. High-dose epinephrine is harmful and is not recommended. Epinephrine may improve return of spontaneous circulation, but does not improve survival to discharge or neurologic outcome. Literature suggests that three phases of resuscitation are present: electrical, circulatory, and metabolic. Epinephrine may improve outcomes in the circulatory phase prior to 10 min post arrest, though further study is needed. Basic Life Support measures including adequate chest compressions and early defibrillation provide the greatest benefit. ConclusionsEpinephrine may improve return of spontaneous circulation, but it does not improve survival to discharge or neurologic outcome. Timing of epinephrine may affect patient outcome, but Basic Life Support measures are the most important aspect of resuscitation and patient survival.

Family Burden After Out-of-Hospital Cardiac Arrest in Children.

To describe family burden among caregivers of children who survived out-of-hospital cardiac arrest and who were at high risk for neurologic disability and examine relationships between family burden, child functioning, and other factors during the first year post arrest. Secondary analysis of data from the Therapeutic Hypothermia after Pediatric Cardiac Arrest Out-of-Hospital trial. Thirty-six PICUs in the United States and Canada. Seventy-seven children recruited to the Therapeutic Hypothermia after Pediatric Cardiac Arrest Out-of-Hospital trial who had normal prearrest neurologic functioning and were alive 1 year post arrest. Family burden was assessed using the Infant Toddler Quality of Life Questionnaire for children less than 5 years old and the Child Health Questionnaire for children 5 years old or older at baseline (reflecting prearrest status), 3 months, and 12 months post arrest. Child functioning was assessed using the Vineland Adaptive Behavior Scale II, the Pediatric Overall Performance Category, and Pediatric Cerebral Performance Category scales and caregiver perception of global functioning. Fifty-six children (72.7%) were boys, 48 (62.3%) were whites, and 50 (64.9%) were less than 5 years old prior to out-of-hospital cardiac arrest. Family burden at baseline was not significantly different from reference values. Family burden was increased at 3 and 12 months post arrest compared with reference values (p < 0.001). Worse Pediatric Overall Performance Category and Pediatric Cerebral Performance Category, lower adaptive behavior, lower global functioning, and higher family burden all measured 3 months post arrest were associated with higher family burden 12 months post arrest (p < 0.05). Sociodemographics and prearrest child functioning were not associated with family burden 12 months post arrest. Families of children who survive out-of-hospital cardiac arrest and have high risk for neurologic disability often experience substantial burden during the first year post arrest. The extent of child dysfunction 3 months post arrest is associated with family burden at 12 months.

Targeted temperature management in cardiovascular disease complicated by cardiac arrest.

The majority of cardiac arrests occur due to cardiovascular etiology. Targeted temperature management (TTM) (32-34°C) is a part of the standard post arrest care. We hypothesized that lower body temperature may lead to reduced cardiac metabolic demand and potentially have a beneficial effect on myocardial function. We performed a retrospective study on patients admitted to the intensive care unit following cardiac arrest secondary to cardiovascular etiology over a 9year period. We assessed the impact of TTM on neurological and cardiac outcomes. There were 57 patients in the cohort; 21 patients in the TTM group and 36 in the non-TTM group. Demographic characteristics were similar in both groups-the majority of patients (86 vs 80%, respectively) were males in their 60s. Neurological outcomes were similar; 24% of patients died during the ICU admission in the TTM group vs 18% in the non-TTM group. Mean GCS on admission to the ICU was 4 vs 7, respectively, and 11 at discharge in both groups. Majority of patients recovered good neurological function (GCS≥13)-57% in the TTM group vs 64% in the non-TTM group. The change in left ventricular function over a 6month follow up period was significantly better in patients who received targeted temperature management-mean change of +4.4 vs -3.3%, respectively. This proved to be statistically significant (p=0.02). The study demonstrates a possible beneficial effect of TTM on long-term cardiac function, when instituted following cardiac arrest.

Abstract 10900: Persistent Alterations in Energy Metabolism and Oxygen Consumption Following Cardiac Arrest

Introduction: Although metabolic problems after cardiac arrest (CA) have been postulated, the actual measurement of metabolic alterations after CA remain undescribed. The measurement of oxygen extraction (VCO2), carbon dioxide excretion (VCO2), and respiratory quotient (RQ), reflect the energy metabolism and may provide insight into the post-arrest metabolism. Objective: To investigate metabolism alterations after CA, which may be detected via changes in VCO2, VO2, and RQ. Secondarily to test whether it is affected by therapeutic temperature management (TTM) Methods: Sixteen male rats underwent a protocol for 10 minutes of asphyxial CA and return of spontaneous circulation (ROSC). Three groups were compared: Group1: controls (no-CA, n=5), group2: CA (n=6), and group3: CA with TTM (n=5). Within the TTM group, the body was cooled to 33 °C. Capnography was recorded and O2 extraction was measured for 120min to measure VCO2 and VO2. RQ was the ratio of VCO2/VO2. Results: The post arrest VCO2 was 1.5 fold higher in the CA group than in the controls (17.3±2.2mL/kg/min versus 11.2±1.0mL/kg/min, p&lt;.01) in minutes 20 through 60. The VCO2 value in CA was normalized after 60min. VCO2 (12.5±1.3 mL/kg/min, p&lt;.01) in TTM-treated CA was significantly lower than untreated CA. The post arrest VO2 was greater in the CA group than in the controls, starting 15min after ROSC, and gradually increased to an extraction rate 2.1 fold higher (29.8±6.0mL/kg/min) than controls (14.1±1.6mL/kg/min, p&lt;.01). There were no differences in VO2 between TTM-treated and untreated CA. RQs in TTM-treated and untreated CA were significantly and persistently lower than controls (0.5±0.1, 0.5±0.1 vs. 0.9±0.1, p&lt;.01). Conclusions: VO2 in rats after CA was markedly elevated after ROSC and RQ decreased to extremely low levels. VCO2 showed some attenuation by TTM, however surprisingly TTM did not affect VO2 or RQ. These results suggest that profound alterations in oxygen extraction occur after CA and may be measured non-invasively in patients. The finding of a lowered RQ has not be described previously, appears to be driven by increased VO2, and may be due to non-CO2 generating oxygen utilization. If true, this may have great importance for mechanism, monitoring, and customized treatment of CA.

Abstract 18554: Patient, Cardiac Arrest and Hospital Characteristics That Predict Receipt of Coronary Angiography in Out-of-Hospital Cardiac Arrest Patients

Introduction: Previous studies have suggested an association between coronary angiography and improved outcomes amongst post cardiac arrest patients. Our objective was to measure the association between patient and hospital-level characteristics and receipt of coronary angiography to generate hypotheses to inform a definitive trial. Methods: This was a population-based retrospective cohort study of data from 28 hospitals in Southern Ontario between March 1, 2010 and December 31, 2014. We included consecutive adult patients with atraumatic, OHCA, who achieved return of spontaneous circulation, and were alive 6 hours after hospital arrival. Multi-level logistic regression was used to measure the relationship between patient and hospital-level covariates and receipt of coronary angiography, adjusted for clustering and potential confounders. Results: During the period of study, 2678 consecutive patients met the inclusion criteria; mean age 66(±16), 68.3% male, 45.9% shockable initial rhythm, 84.2% comatose at hospital admission. Overall, 32.4% received coronary angiography and 21.8% received percutaneous coronary intervention (PCI). Coronary angiography use varied from 12.7% to 63.6% across the sites. Factors significantly associated with receiving coronary angiography included ST-elevation (OR=23.31, CI95 17.64-30.80), being comatose at hospital arrival (OR=0.15, CI95 0.10-0.23), shockable initial cardiac rhythm (OR=4.87, CI95 3.70-6.41), bystander AED use (OR=2.05, CI95 1.21-3.47), EMS-witnessed arrest (OR=1.80, CI95 1.16-2.78), initiation of therapeutic hypothermia (OR=1.96, CI95 1.38-2.79), initial admission to a PCI centre (OR=3.20, CI95 1.78-5.76), male sex (OR=1.43, CI95 1.07-1.90) and age (OR=0.98, CI95 0.97-0.99). Conclusions: There is significant variability in receipt of coronary angiography after cardiac arrest. We identified several patient and hospital-level factors that contribute to this variability. Future work should determine which post arrest patients will benefit most from urgent angiography and develop and evaluate knowledge translation strategies to ensure consistent delivery of best practices.

Abstract 18724: Coronary Angiography After Out-of-hospital Cardiac Arrest is Associated With Improved Neurologically Intact Survival

Introduction: Evidence for the effectiveness of coronary angiography after out-of-hospital cardiac arrest (OHCA) is conflicting. Our objective was to evaluate the association between receiving coronary angiography within 72 hours of hospital arrival and survival with favorable neurologic outcome. Methods: This was a population-based retrospective cohort study of consecutive cases of adult OHCA transported to and treated at 28 hospitals in Southern Ontario between March 1, 2010 and December 31, 2014. We included patients with atraumatic OHCA, who achieved return of spontaneous circulation, and were alive 6 hours after hospital arrival. Multi-level logistic regression was used to measure the association between early coronary angiography and neurologically intact survival (Modified Rankin Score 0-2), while controlling for potential confounders and clustered data. We controlled for age, sex, initial cardiac rhythm, witness status, bystander resuscitation, EMS response time, prehospital return of spontaneous circulation, location of arrest, daytime presentation, neurologic status at hospital arrival, STEMI status, cardiac history, initiation of therapeutic hypothermia, hospital size and type, and hospital annual cardiac arrest volume. Results: During the period of study, 2678 consecutive OHCA patients met the inclusion criteria. The mean age was 66(±16), 31.7% were female, 54.1% had a bystander witnessed arrest, 35.2% received bystander CPR, 45.9% had a shockable initial rhythm, 30.1% had ST elevation on the first post arrest ECG, and 32.4% received coronary angiography. Receiving coronary angiography was strongly associated with neurologically intact survival (OR 2.30, CI95 1.69-3.15) and survival (OR 2.08, CI95 1.53-2.82). A similar association was observed in the subgroup of patients without STEMI (OR 3.24, CI95 2.16-4.87 and OR 2.66, CI95 1.78-3.99, respectively). Conclusions: Neurologically intact survival among post cardiac arrest patients may be improved with coronary angiography, particularly for patients without STEMI. This observation should be confirmed with future randomized controlled studies.

Abstract 14379: Variation of Percutaneous Coronary Intervention in Patients Resuscitated From Out-of-Hospital Cardiac Arrest- A Statewide Evaluation

Our primary objective is to describe the use of percutaneous coronary intervention (PCI) in patients resuscitated from OHCA using a probabilistic linked statewide EMS and hospital dataset. A secondary objective was to compare variations of care rendered by hospitals across Michigan. We performed a retrospective study to describe PCI use in Adult (&gt;18 years) OHCA patients resuscitated and transported to Michigan hospitals July 1, 2010 to June 30, 2013. We linked two databases , the Michigan EMS Information System (MI_EMSIS) and the Michigan Inpatient Database (MIDB), using a previously validated methodology to create our dataset. Inter-hospital transfers, duplicate cases, and cases with missing arrest rhythms were excluded. This dataset was queried for patient demographics, EMS cardiac arrest variables, provision of PCI, clinical characteristics(VF, cardiogenic shock (Cshock)), hospital diagnosis (AMI) and outcome. Rates of procedure are reported in aggregate and stratified by clinical characteristics, and, to assess the impact of geography on emergency care by the eight Michigan Emergency Care regions. During the study period there were 2,855 matched EMS and MHA records, of which 32.1% survived to hospital discharge. PCI was almost exclusively performed in patients with AMI (38.7% vs 1.6%, (OR=39.0, 95% CI 26.7, 56.8). Clinical factors associated with PCI included initial VF (21.6% vs 9.5%, OR=2.6, 95% CI (2.1,3.3) or Cshock (28.6% vs 8.7%, OR=4.2, 95% CI 3.3, 5.3) Rates of PCI statewide and by region are reported in the table and demonstrate significant variation by region. Conclusion: We identified relatively low rates of PCI for post arrest patients, which was performed primarily for patients with final diagnosis AMI. Patients with initial VF, or cardiogenic shock were more likely to receive PCI. While geographic factors impact post cardiac arrest care, we observe that a minority of post arrest patients in Michigan receive aggressive reperfusion care.

Abstract 15924: Early Non-contrast Head Computed Tomography for Prognostication of Neurologic Outcomes Following Cardiac Arrest

Introduction: Prognostication of neurologic outcomes in patients achieving return of spontaneous circulation (ROSC) following cardiac arrest poses a difficult challenge. A low ratio of gray matter to white matter (GWR) attenuation on early non-contrast head computed tomography (NCHCT) may be a specific predictor of poor neurologic outcome following arrest. We sought to validate this finding and to determine if there is a GWR cutoff that is completely specific for predicting poor neurologic outcomes. Methods: We identified 145 patients from our institution with a cardiac arrest between February 2007 and March 2015 who underwent NCHCT within 24 hours following ROSC. GWRs were calculated by measuring the attenuation of 10-15 mm 2 regions of interest in Hounsfield units, identifying the head of the caudate nucleus for gray matter and the posterior limb of the internal capsule for white matter. Neurologic outcomes were recorded by cerebral performance category (CPC) upon hospital discharge. A CPC score of 1 or 2 defined a favorable neurologic outcome, whereas a score of 3, 4, or 5 marked a poor neurologic outcome. Results: Fifty patients had favorable neurologic outcomes, with a median GWR of 1.29 and an interquartile range (IQR) of 1.24-1.34. Ninety-five patients had poor neurologic outcomes, with a median GWR of 1.25 and an IQR of 1.18-1.30. Performance of the GWR as a predictor of neurologic outcome was examined by plotting a receiver operating characteristic curve; the area under the curve was 0.658. However, a GWR below 1.16 was found to have 100% specificity for predicting a poor neurologic outcome following arrest (20 cases, 21.1% sensitivity). Conclusion: In our study, a GWR below 1.16 was shown to be a completely specific predictor of poor neurologic outcome following cardiac arrest. In combination with other modalities, GWR on NCHCT could help guide management by lending prognostic information early in the post arrest course.

Abstract 17799: Have We Abandoned Therapeutic Hypothermia Prematurely?

Introduction: Following the recent Targeted Temperature Management (TTM) Trial, many worldwide cardiac arrest centers have adjusted target temperatures from 330C to 360C. The aim of this study was to examine quality of post-arrest care in an expert cardiac center following the adoption of a TTM protocol. Methods: We conducted an audit of consecutive ventricular fibrillation out-of-hospital cardiac arrest (VF-OHCA) patients of presumed cardiac etiology, admitted to a quaternary referral cardiac hospital in Australia. Results: Over the two-year period there were 70 VF-OHCAs admitted (28 before TTM change and 42 after). Patient demographics, arrest features including witnessed arrest, bystander CPR and arrest duration were all similar, between the two periods. Post-arrest care including cardiology consults (93% vs 100%, p=0.15), coronary angiography (79% vs. 76%, p=0.82) and documented orders for TTM were all equivalent. Compliance, however, with temperature management was significantly worse in the 360C period; the average time at target temperature was significantly lower in this time (22hrs vs. 8hrs, p&lt;0.001). 50% of patients recorded temperatures &gt;37.1o in the first 24-hours in the 360C, compared to 0% of patients during the 330C period. Survival to hospital discharge (75% vs 69%, p = 0.59) and rates of discharge to home among (59% vs 45%, p = 0.32) were similar between 330C and 360C periods. After adjustment for arrest duration, an abnormal temperature (&gt;37.10C) in the first 24hours following hospital admission was associated with hypoxic brain injury (AOR=4.55, 95%CI: 1.08-19.09, p=0.039). Conclusion: Revision of the TTM protocol in an expert cardiac centre was associated with significant non-compliance with target temperatures, leading to increased febrile patients in the post arrest period and possible poorer outcomes.

Abstract 15333: Choosing Where to Live or Die: Regional Variation in Outcomes Following Out-of-hospital Cardiac Arrest (OHCA) in the United States

Background: Regional Differences in health outcomes following OHCA has been poorly studied, and was the focus of this investigation. Methods: We used the 2002 to 2012 Nationwide Inpatient Sample database to identify adults ≥ 18 years old, with an ICD-9 code principal diagnosis of cardio respiratory arrest (427.5) or ventricular fibrillation (427.1). Trauma patients were excluded. In 4 predefined federal geographic regions: North East, Midwest, South and West, means and proportions of total hospital charges (adjusted to the 2012 consumer price index,) and mortality rate were calculated. Multiple linear and logistic regression models, were adjusted for patient demographics, hospital characteristics and Charlson Comorbidity Index. Trends in binary outcome were examined with YearхRegion interaction terms. Results: From 2002 to 2012, of 155,592 OHCA patients who survived to hospital admission , 26,007 (16.7%) were in the Northeast, 39,921 (25.7% ) in the Midwest, 56,263 (36.2%) in the South, and 33,401 (21.5% ) in the West. Total hospital charges (THC) rose significantly over the years across all regions of the United States ( P trend &lt;0.0001), and were higher in the West Vs the North East (THC&gt;$109,000/admission, AOR 1.85; 95% CI 1.53-2.24, p&lt;0.0001), and not different in other regions. Compared to the Northeast, mortality was lower in the Midwest ( AOR 0.86, 95% CI 0.77-0.97 p=0.01), marginally lower in the South ( AOR 0.91, 95% CI 0.82-1.01 p=0.07), with no difference detected between the West and the Northeast ( AOR 1.02, 95% CI 0.90-1.16 P=0.78). Increased expenditure was not rewarded by an increase in survival, as trends in Mortality did not differ significantly between regions (YearхRegion effects P&gt;0.05, P trend =0.29). Conclusions: Nationwide, there is a considerable variability in survival and charges associated with caring for the post arrest patient. Higher charges did not yield better outcomes. Further investigation is needed to optimize health care delivery.

Evaluation of biomarkers and use of echocardiography in survival prognosis post cardio-respiratory arrest

Information on biomarkers dynamics during and immediately after cardiopulmonary resuscitation (CPR) are limited and fragmented. Along with clinical data, some biomarkers and intracardiac volume changes assessed by transthoracic echocardiography can provide important prognostic information especially if measurements are made early, even at the event.

Cardiac myocardial damage associated with resuscitation

Purpose of study: In the event of sudden cardiac arrest, the 2010 American Heart Association (AHA) guidelines recommend defined cardiopulmonary resuscitation (CPR) compression depths and defibrillation energies for both paediatric (<8 yrs) and adult patients for patient recovery. However there is limited information regarding the damaging effects of resuscitation on the tissues of the heart at a structural and genomic level. This study investigated the extent of gross and microscopic structural cardiac damage associated with implementing the 2010 AHA guidelines in a porcine model of cardiac arrest.Materials and methods: Ventricular fibrillation (VF) was induced in paediatric and adult porcine models. Following defibrillation and CPR as per the recommended guidelines, tissue samples were collected. Structural changes in the myocardial tissue were assessed using standard histological staining and ultrastructural damage to the tissues assessed using electron microscopy (EM). RNA was extracted from tissue samples and quantitative real time-PCR was performed to assess the mRNA expression of key genes associated with early markers of cardiovascular damage (troponin-1, DES, IL6, FABP3, Cx43). Clinical biomarker expression levels of Troponin I were also quantified pre and post treatment via the Vet iStat (Abaxis, USA).Results: All animals sustained gross structural damage including broken ribs, 3 animals had perforated atria and considerable damage to the ventricles was evident in the histological specimens. EM analysis revealed minor modifications in the ultrastructural appearance of the myocardial tissues. An increase in cardiac troponin-1 was observed in both adult and paediatric models post-resuscitation.Conclusions: This study highlights the extent of myocardial damage at a structural and genomic level, associated with implementing current resuscitation guidelines. It is evident that more research is needed to review the specificity and sensitivity of resuscitation to assist in determining the best method of post arrest treatment that increases the chance of resuscitation with minimal consequential damage.

46. Nurses perception of rapid response team in a tertiary hospital in Saudi Arabia

For the last 30 years, the goal of improving the survival rate for patients post cardiopulmonary arrest has remained unattainable. This apparent failure to rescue opened the door to devise new strategies to improve patient outcomes at the onset of subtle deterioration, rather than at the point of cardiac arrest. Institute for Healthcare Improvement (IHI) introduced the Rapid Response Team (RRT) as one of the six preventative steps to save lives. Nurses’ perceptions of the RRT influenced by the content and process support provided. Nurses are responsible to detect the early signs of deterioration, and activate the RRT service. The aim of this cross sectional descriptive study was to examine nurses’ perceptions about the effect of the RRT and perceived content and process support in managing patient deterioration by using mental model maintenance and building at individual, group and hospital levels in a tertiary hospital in the Kingdom of Saudi Arabia. 300 nurses were recruited using a convenience sampling method. The study findings showed that the overall perceptions about the RRT were high. There was a significant positive correlation between the frequent utilization of the RRT and the perceived content support. The analysis of the open ended questions indicated that there were more advantages to have the RRT service than disadvantages. This study suggested that RRT service is influential in improving nurses’ perceptions about managing Patients’ deterioration. Training program about RRT utilization should include both content and process support, which may enhance building and maintaining mental model.