Initial end-tidal carbon dioxide as a predictive factor for return of spontaneous circulation in nonshockable out-of-hospital cardiac arrest patients: A retrospective observational study.

BACKGROUND: Early outcome prediction in out-of-hospital cardiac arrest is still a challenge. End-tidal carbon dioxide (ETCO2) has been shown to be a reliable parameter to reflect the quality of cardiopulmonary resuscitation and the chance of return of spontaneous circulation (ROSC). OBJECTIVES: This study assessed the validity of early capnography as a predictive factor for ROSC and survival in out-of-hospital cardiac arrest victims with an underlying nonshockable rhythm. DESIGN: Retrospective observational study. SETTING/PATIENTS: During a 2-year observational period, data from 2223 out-of-hospital cardiac arrest victims within the city of Vienna were analysed. The focus was on the following patients: age more than 18 years, an underlying nonshockable rhythm, and advanced airway management within the first 15 min of advanced life support with subsequent capnography. INTERVENTION: No specific intervention was set in this observational study. MAIN OUTCOME MEASURES: The first measured ETCO2, assessed immediately after placement of an advanced airway, was used for further analysis. The primary outcome was defined as sustained ROSC, and the secondary outcome was 30-day survival. RESULTS: A total of 526 patients met the inclusion criteria. These were stratified into three groups according to initial ETCO2 values (<20, 20 to 45, >45 mmHg). Baseline data and resuscitation factors were similar among all groups. The odds of sustained ROSC and survival were significantly higher for patients presenting with higher values of initial ETCO2 (>45 mmHg): 3.59 [95% CI, 2.19 to 5.85] P = 0.001 and 5.02 [95% CI, 2.25 to 11.23] P = 0.001, respectively. On the contrary ETCO2 levels less than 20 mmHg were associated with significantly poorer outcomes. CONCLUSION: Patients with a nonshockable out-of-hospital cardiac arrest who presented with higher values of initial ETCO2 had an increased chance of sustained ROSC and survival. This finding could help decision making as regards continuation of resuscitation efforts.

Age-dependent effect of targeted temperature management on outcome after cardiac arrest.

BACKGROUND: In elder patients after out-of-hospital cardiac arrest, diminished neurologic function as well as reduced neuronal plasticity may cause a low response to targeted temperature management (TTM). Therefore, we investigated the association between TTM (32-34°C) and neurologic outcome in cardiac arrest survivors with respect to age. MATERIAL AND METHODS: This retrospective cohort study included patients 18 years of age or older suffering a witnessed out-of-hospital cardiac arrest with presumed cardiac cause, which remained comatose after return of spontaneous circulation. Patients were a priori split by age into four groups (<50 years (n = 496); 50-64 years (n = 714); 65-74 years (n = 395); >75 years (n = 280)). Subsequently, within these groups, patients receiving TTM were compared to those not treated with TTM. RESULTS: Out of 1885 patients, 921 received TTM for 24 hours. TTM was significantly associated with good neurologic outcome in patients <65 years of age whereas showing no effect in elders (65-74 years: OR: 1.49 (95% CI: 0.90-2.47); > 75 years: OR 1.44 (95% CI 0.79-2.34)). CONCLUSION: In our cohort, it seems that TTM might not be able to achieve the same benefit for neurologic outcome in all age groups. Although the results of this study should be interpreted with caution, TTM was associated with improved neurologic outcome only in younger individuals, patients with 65 years of age or older did not benefit from this treatment.

A case report of septic shock syndrome caused by S. pneumoniae in an immunocompromised patient despite of vaccination.

BACKGROUND AND CASE PRESENTATION: We report a case of septic shock syndrome caused by Streptococcus pneumoniae in a patient who had undergone splenectomy due to an autoimmune lymphoproliferative syndrome (ALPS), which is characterized as a dysfunction of immunoregulation. Although the patient was vaccinated with a conjugated polysaccharide vaccine after the splenectomy, he was still susceptible to S. pneumoniae infection, because the isolated serovar (24F), a serovar long thought to be apathogenic, is not covered by any vaccine currently approved, neither a conjugated nor an unconjugated polysaccharide one. CONCLUSIONS: This case demonstrates that, due to presence of different serovars, also infections with bacteria against which patients are vaccinated have to be considered as differential diagnosis. Although vaccine development has extended the coverage of S. pneumoniae from 7 to 23 serovars within recent years, there is still demand for novel vaccines which can provide broader protection also against so-thought "apathogenic" strains, especially for groups at high risk.

Reduced long-term memory in a rat model of 8 minutes ventricular fibrillation cardiac arrest: a pilot trial.

BACKGROUND: Evaluating beneficial effects of potential protective therapies following cardiac arrest in rodent models could be enhanced by exploring behavior and cognitive functions. The Morris Water Maze is a well-known cognitive paradigm to test spatial learning and memory. RESULTS: Behavioral testing with the Morris Water Maze in Sprague-Dawley rats (300 ± 25 g) resuscitated after 8 min of ventricular fibrillation cardiac arrest was carried out 5 and 12 weeks after cardiac arrest (CA) and compared to results of naïve rats (CONTROL). At 5 weeks, within each group latency time to reach the hidden platform (reflecting spatial learning) decreased equally from day 1 to 4 (CA: 105.6 ± 8.2 vs. 8.9 ± 1.2 s, p < 0.001; CONTROL: 75.5 ± 13.2 vs. 17.1 ± 4.5, p < 0.001) with no differences between groups (p = 0.138). In the probe trial 24 h after the last trial, time spent in the target sector (reflecting memory recall) within each group was significantly longer (CA: 25 ± 1.3; CONTROL: 24.7 ± 2.5 s) than in each of the three other sectors (CA: 7.7 ± 0.7, 14.3 ± 2.5, 8.4 ± 0.8 and CONTROL: 7.8 ± 1.2, 11.7 ± 1.5, 10.3 ± 1.6 s) but with no significantly differences between groups. Seven days later (reflecting memory retention), control group animals remained significantly longer in the target sector compared to every other sector, whereas the cardiac arrest group animals did not. Even 12 weeks after cardiac arrest, the single p values showed that the control animals displayed a trend to perform better than the resuscitated animals. CONCLUSIONS: Memory recall was impaired early after 8 min of ventricular fibrillation cardiac arrest and might be a more valuable tool for cognitive testing than learning recall after global ischemia due to cardiac arrest.

Cardiac arrest caused by acute intoxication-insight from a registry.

INTRODUCTION: The aim of the study was to evaluate the epidemiology and outcome after cardiac arrest caused by intoxication. METHODS: A retrospective analysis of 1991 to 2010 medical record of patients experiencing cardiac arrest caused by self-inflicted, intentional intoxication was performed. The setting was an emergency department of a tertiary care university hospital. The primary end point was the presentation of epidemiologic data in relation to favorable neurologic outcome, defined as cerebral performance categories 1 or 2 and 180-day survival. Furthermore, the patients were subdivided into a single-substance and polysubstance group, depending on the substances causing the intoxication. RESULTS: Of 3644 patients admitted to our department, 99 (2.7%) with a median age of 26 (interquartile range, 19-42) years (37% female) were included. Cardiac arrest was witnessed in 62 cases (63%). Eleven patients (11%) received basic life support by bystanders, and 11 (11%) had a shockable rhythm in the initial electrocardiogram. The combined end point "good survival" was achieved by 34 patients (34%). Cardiac arrest occurred out of hospital in 73 patients (74%) and in-hospital in 26 patients (26%). A single substance causing the intoxication was found in 56 patients (56%). Opiates were the leading substance, with 25 patients (25%) using them. CONCLUSION: Cardiac arrest caused by intoxication is found predominately in young patients. Overall, favorable neurologic survival was achieved in 34%. Opiate-related cardiac arrest was associated with poor survival and a high incidence of neurologic deficits.

Resuscitative transoesophageal echocardiography performed by emergency physicians in the emergency department: insights from a 1-year period.

AIMS: Transoesophageal echocardiography (TOE) has increasingly been described as a possible complementary and point-of-care approach for patients with cardiac arrest (CA). It provides information about potentially reversible causes and prognosis and allows monitoring of resuscitation efforts without affecting ongoing chest compressions. The aim of this study was to assess the feasibility of TOE performed by emergency physicians (EPs) during CA in an emergency department (ED). METHODS AND RESULTS: This prospective study was performed at the Department of Emergency Medicine at the Medical University of Vienna from February 2020 to February 2021. All patients of ≥18 years old presenting with ongoing resuscitation efforts were screened. After exclusion of potential contraindications, a TOE examination was performed and documented by EPs according to a standardized four-view imaging protocol. The primary endpoint represents feasibility defined as successful probe insertion and acquisition of interpretable images. Of 99 patients with ongoing non-traumatic CA treated in the ED, a total of 62 patients were considered to be examined by TOE. The examination was feasible in 57 patients (92%) [females, 14 (25%), mean age 53 ± 13, and witnessed collapse 48 (84%)]. Within these, the examiners observed 51 major findings in 32 different patients (66%). In 21 patients (37%), these findings led to a direct change of therapy. In 18 patients (32%), the examiner found ventricular contractions without detectable pulse. No TOE-related complications were found. CONCLUSION: Our findings suggest that EPs may be able to acquire and interpret TOE images in the majority of patients during CA using a standardized four-view imaging protocol.

Mild therapeutic hypothermia improves outcomes compared with normothermia in cardiac-arrest patients--a retrospective chart review.

OBJECTIVE: Studies showing the effectiveness of therapeutic hypothermia (32-34°C) in postcardiac arrest patients have been criticized because of patients with elevated body temperature (>37.5°C) in the noncooled control group. Thus, the effects of spontaneous normothermia (<37.5°C) compared with mild therapeutic hypothermia were studied. DESIGN: Retrospective chart review from 1991 to 2010. PATIENTS: Witnessed out-of-hospital arrest, presumed to be of cardiac origin, aged 18 to 80 yrs and with a Glassgow Coma Scale score of <8 at admission. INTERVENTIONS: Patients with sustained restoration of spontaneous circulation who did not receive therapeutic hypothermia and never exceeded 37.5°C during the 36 hrs postcardiac arrest were compared with patients who received mild therapeutic hypothermia. MEASUREMENTS AND MAIN RESULTS: The primary end point was a favorable neurological outcome, defined as Cerebral Performance Categories 1 or 2; the secondary end point was overall survival to 180 days. Significantly more patients in the hypothermia group had Cerebral Performance Categories 1 or 2 (hypothermia: 256 of 467 [55%] vs. normothermia: 69 of 165 [42%]) and survived for >180 days (hypothermia: 315 of 467 [67%] vs. normothermia: 79 of 165 [48%]). The propensity score adjusted risk ratio for good neurological outcome of patients undergoing hypothermia treatment was 1.37 (confidence interval 1.09-1.72, p≤.01) and for dying within 180 days was 0.57 (confidence interval 0.44-0.73, p≤.01) compared to normothermia. CONCLUSIONS: Therapeutic hypothermia is associated with significantly improved neurological outcome and 180-day survival compared to spontaneous normothermia in cardiac-arrest patients.

Culprit site extracellular DNA and microvascular obstruction in ST-elevation myocardial infarction.

AIMS: Extracellular chromatin and deoxyribonuclease (DNase) have been identified as important players of thrombosis, inflammation, and homeostasis in a murine model. We previously demonstrated that activated neutrophils release neutrophil extracellular traps (NETs) at the culprit site in ST-elevation myocardial infarction (STEMI), which significantly contribute to extracellular chromatin burden, and are associated with larger infarcts. To understand the correlation between neutrophil activation, extracellular chromatin, and infarct size (IS), we investigated these parameters in a porcine myocardial infarction model, and at different time points and sites in a prospective STEMI trial with cardiac magnetic resonance (CMR) endpoints. METHODS AND RESULTS: In a prospective STEMI trial (NCT01777750), 101 STEMI patients were included and blood samples were obtained from first medical contact until 6 months after primary percutaneous coronary intervention (pPCI) including direct sampling from the culprit site. CMR was performed 4 ± 2 days and 6 months after pPCI. Neutrophil counts, markers of extracellular chromatin, and inflammation were measured. Double-stranded deoxyribonucleic acid (dsDNA), citrullinated histone 3, nucleosomes, myeloperoxidase, neutrophil elastase, and interleukin (IL)-6 were significantly increased, while DNase activity was significantly decreased at the culprit site in STEMI patients. High neutrophil counts and dsDNA levels at the culprit site correlated with high microvascular obstruction (MVO) and low ejection fraction (EF). High DNase activity at the culprit site correlated with low MVO and high EF. In correspondence, dsDNA correlated with IS in the porcine myocardial infarction model. In porcine infarcts, neutrophils and extracellular chromatin were detected in congested small arteries corresponding with MVO. Markers of neutrophil activation, extracellular chromatin, DNase activity and CMR measurements correlated with markers of systemic inflammation C-reactive protein and IL-6 in patients. CONCLUSIONS: NETs and extracellular chromatin are important determinants of MVO in STEMI. Rapid degradation of extracellular chromatin by DNases appears to be crucial for microvascular patency and outcome.

Surface cooling for induction of mild hypothermia in conscious healthy volunteers - a feasibility trial.

INTRODUCTION: Animal and human studies suggest beneficial outcome effects of mild hypothermia for stroke, for acute myocardial infarction, and for cardiogenic shock. The aim of this study was to investigate the feasibility and safety of non-invasive surface cooling for induction and maintenance of mild hypothermia (32 to 34°C) in healthy, conscious volunteers. METHODS: The trial was set at a clinical research ward in a tertiary care center, and included 16 healthy male volunteers 18 to 70 years old. Surface cooling was established by a novel non-invasive cooling pad with an esophageal target temperature of 32 to 34°C and maintenance for six hours. Shivering-control was achieved with meperidine and buspirone and additional administration of magnesium in eight subjects. RESULTS: The primary endpoint to reach a target temperature of 32 to 34°C was only reached in 6 of the 16 participating subjects. Temperatures below 35°C were reached after a median cooling time of 53 minutes (38 to 102 minutes). Cooling rate was 1.1°C/h (0.7 to 1.8°C). Additional administration of magnesium had no influence on cooling rate. At no time during the cooling procedure did the participants report uncomfortable conditions for which termination of cooling had to be considered. No severe skin damage was reported. CONCLUSIONS: Cooling to body temperature below 35°C by the use of non-invasive surface cooling is feasible and safe in conscious healthy volunteers. Further studies are needed to investigate an altered cooling protocol to achieve temperatures below 35°C. TRIAL REGISTRATION: ISRCTN: ISRCTN50530495.

Relationship between time to target temperature and outcome in patients treated with therapeutic hypothermia after cardiac arrest.

INTRODUCTION: Our purpose was to study whether the time to target temperature correlates with neurologic outcome in patients after cardiac arrest with restoration of spontaneous circulation treated with therapeutic mild hypothermia in an academic emergency department. METHODS: Temperature data between April 1995 and June 2008 were collected from 588 patients and analyzed in a retrospective cohort study by observers blinded to outcome. The time needed to achieve an esophageal temperature of less than 34°C was recorded. Survival and neurological outcomes were determined within six months after cardiac arrest. RESULTS: The median time from restoration of spontaneous circulation to reaching a temperature of less than 34°C was 209 minutes (interquartile range [IQR]: 130-302) in patients with favorable neurological outcomes compared to 158 min (IQR: 101-230) (P < 0.01) in patients with unfavorable neurological outcomes. The adjusted odds ratio for a favorable neurological outcome with a longer time to target temperature was 1.86 (95% CI 1.03 to 3.38, P = 0.04). CONCLUSIONS: In comatose cardiac arrest patients treated with therapeutic hypothermia after return of spontaneous circulation, a faster decline in body temperature to the 34°C target appears to predict an unfavorable neurologic outcome.

Mild Therapeutic Hypothermia Alters Hemostasis in ST Elevation Myocardial Infarction Patients.

Background and Rationale: Mild therapeutic hypothermia (MTH) is a concept to reduce infarct size and improve outcome after ST-segment elevation myocardial infarction (STEMI). In the STATIM trial, we investigated MTH as an additional therapy for STEMI patients. In the intention-to-treat set, 101 patients were included. No difference in primary and secondary endpoints measured by cardiac magnetic resonance imaging was found. Platelet activation and plasmatic coagulation are key in the pathophysiology of STEMI. In the present study, we investigated the effect of MTH on primary and secondary hemostasis in STEMI patients. Methods and Results: Platelet function and morphology were assessed by routine blood count, aggregometry testing, and flow cytometry. Soluble platelet markers were determined by enzyme-linked immunosorbent assay (ELISA) testing. Plasmatic coagulation was measured throughout the study. Platelet count remained unchanged, irrespective of treatment, whereas platelet size decreased in both patient groups. Platelet aggregometry indicated increased platelet reactivity in the MTH group. Furthermore, higher adenosine diphosphate (ADP) plasma levels were found in MTH patients. Expression of glycoprotein IIb/IIIa was increased on platelets of STEMI patients treated with MTH. Lower patient temperatures correlated with longer clotting times and resulted in reduced pH. Lower pH values were positively correlated with longer clotting times. Conclusion: Present data indicate longer clotting times and higher platelet reactivity in STEMI patients treated with MTH. These changes did not correspond to clinical bleeding events or larger infarct size.

Copeptin Levels Are Independent from Mild Therapeutic Hypothermia but Do Not Predict Infarct Size in Patients Presenting with ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Mild therapeutic hypothermia (MTH) is a treatment adjunct in ST-segment elevation myocardial infarction (STEMI) that deserves investigation. Copeptin-a surrogate marker for vasopressin-is an early biomarker in STEMI. Data from cardiac arrest patients suggest a reduction of copeptin levels through MTH; however, copeptin levels have not been investigated in MTH during STEMI. METHODS: We analyzed patients treated with MTH during STEMI in a sub-study of the STATIM trial (Testori, Heart 2019). Patients were randomized to normothermia or MTH with out-of-hospital initiation. Seven copeptin samples were collected from each patient. Primary endpoint was the difference in copeptin levels between the groups. As secondary endpoints, we defined differences in the kinetics between the sampling timepoints and the correlation between copeptin and the infarct size in relation to left ventricular myocardium. RESULTS: We included 99 patients (MTH n = 47, control n = 52) in our intention to treat analysis. No differences in copeptin values at first medical contact between the MTH and normothermia groups were found. MTH showed no effect on copeptin levels, neither during cooling phase nor through the course. Copeptin peaked at first medical contact and hospital admission in both groups. No differences in kinetics between the timepoints were found. Copeptin showed no correlation with infarct size, neither at first medical contact nor hospital admission. CONCLUSIONS: Copeptin levels were not influenced by MTH in STEMI, suggesting the use of this biomarker also during temperature management. Furthermore, copeptin levels were not usable as a surrogate marker for infarct size at any timepoint.

Exploratory echocardiographic strain parameters for the estimation of myocardial infarct size in ST-elevation myocardial infarction.

BACKGROUND: Outcome after ST-elevation myocardial infarction (STEMI) can be most reliably estimated by cardiac magnetic resonance (CMR) imaging. However, CMR is expensive, laborious, and has only limited availability. In comparison, transthoracic echocardiography (TTE) is widely available and cost-efficient. HYPOTHESIS: TTE strain parameters can be used as surrogate markers for CMR-measured parameters after STEMI. METHODS: TTE strain analysis was performed of patients included in a controlled, prospective STEMI trial (NCT01777750) 4 ± 2 days after the event. Longitudinal peak strain (LPS), post-systolic shortening, early systolic lengthening, early systolic lengthening time, and time to peak shortening were measured, and index parameters were computed. Global longitudinal strain (GLS) and ejection fraction (EF) were compiled. Parameters were correlated with CMR-measured variables 4 ± 2 days after STEMI. RESULTS: In 70 STEMI patients, high quality CMR and TTE data were available. Highest correlation with CMR-measured infarct size was observed with GLS (r = 0.577, p < 0.0001), LPS (r = 0.571, p < 0.0001), and EF (r = -0.533, p < 0.0001). Highest correlation with CMR-measured area at risk was observed with GLS (r = 0.666, p < 0.0001), LPS (0.661, p < 0.0001) and early systolic lengthening index (r = 0.540, p < 0.0001). Receiver operating characteristics for the detection of large infarcts (quartile with highest infarct size) showed the highest area under the curve for LPS, GLS, EF, and myocardial dysfunction index. Multiple linear regression displayed the best association between GLS and infarct size. CONCLUSION: Exploratory strain parameters significantly correlate with CMR-measured area at risk and infarct size and are of potential interest as endpoint variables in clinical trials.

Percutaneous dilatational tracheotomy in high-risk ICU patients.

BACKGROUND: Percutaneous dilatational tracheotomy (PDT) has become an established procedure in intensive care units (ICU). However, the safety of this method has been under debate given the growing number of critically ill patients with high bleeding risk receiving anticoagulation, dual antiplatelet therapy (DAPT) or even a combination of both, i.e. triple therapy. Therefore, the purpose of this study, including such a high proportion of patients on antithrombotic therapy, was to investigate whether PDT in high-risk ICU patients is associated with elevated procedural complications and to analyse the risk factors for bleeding occurring during and after PDT. METHODS: PDT interventions conducted in ICUs at 12 European sites between January 2016 and October 2019 were retrospectively analysed for procedural complications. For subgroup analyses, patient stratification into clinically relevant risk groups based on anticoagulation and antiplatelet treatment regimens was performed and the predictors of bleeding occurrence were analysed. RESULTS: In total, 671 patients receiving PDT were included and stratified into four clinically relevant antithrombotic treatment groups: (1) intravenous unfractionated heparin (iUFH, prophylactic dosage) (n = 101); (2) iUFH (therapeutic dosage) (n = 131); (3) antiplatelet therapy (aspirin and/or P2Y12 receptor inhibitor) with iUFH (prophylactic or therapeutic dosage) except for triple therapy (n = 290) and (4) triple therapy (DAPT with iUFH in therapeutic dosage) (n = 149). Within the whole cohort, 74 (11%) bleedings were reported to be procedure-related. Bleeding occurrence during and after PDT was independently associated with low platelet count (OR 0.73, 95% CI [0.56, 0.92], p = 0.009), chronic kidney disease (OR 1.75, 95% CI [1.01, 3.03], p = 0.047) and previous stroke (OR 2.13, 95% CI [1.1, 3.97], p = 0.02). CONCLUSION: In this international, multicenter study bronchoscopy-guided PDT was a safe and low-complication airway management option, even in a cohort of high risk for bleeding on cardiovascular ICUs. Low platelet count, chronic kidney disease and previous stroke were identified as independent risk factors of bleeding during and after PDT but not triple therapy.

Temperature monitored on the cuff surface of an endotracheal tube reflects body temperature.

OBJECTIVE: When treating patients with cardiac arrest with mild therapeutic hypothermia, a reliable and easy-to-use temperature probe is desirable. This study was conducted to investigate the accuracy and safety of tracheal temperature as a measurement of body temperature. DESIGN: Observational cohort study. SETTING: Emergency department of a tertiary care university hospital. PATIENTS: Patients successfully resuscitated from cardiac arrest intended for mild hypothermia therapy. INTERVENTIONS: Intubation was performed with a newly developed endotracheal tube that contains a temperature sensor inside the cuff surface. During the cooling, mild hypothermia maintenance, and rewarming phases, the temperature was recorded minute by minute. These data were compared with the temperature assessed by esophageal and blood temperature probes. Thereafter, tracheoscopy was performed to evaluate the condition of the tracheal mucosa. MEASUREMENTS AND MAIN RESULTS: Approximately 2000 measurements per temperature sensor per patient were recorded in 21 patients. The mean bias between the blood temperature and the tracheal temperature was -0.16 degrees C (limits of agreement: -0.36 degrees C to 0.04 degrees C). The mean bias between the esophageal and tracheal temperatures was -0.22 degrees C (limits of agreement: -0.49 degrees C to 0.07 degrees C). Agreement between temperature probes investigated by the Bland-Altman method showed a mean bias of less than -(1/4) degrees C, and time lags assessed graphically by hysteresis plots were negligible. No clinically relevant injury to the tracheal mucosa was detected. CONCLUSION: Temperature monitoring at the cuff surface of an endotracheal tube is safe and provides accurate and reliable data in all phases of therapeutically induced mild hypothermia after cardiac arrest.

Out-of-hospital initiation of hypothermia in ST-segment elevation myocardial infarction: a randomised trial.

OBJECTIVE: To evaluate the effect of prereperfusion hypothermia initiated in the out-of-hospital setting in awake patients with ST-segment elevation myocardial infarction (STEMI) on myocardial salvage measured by cardiac MRI (CMR). METHODS: Hypothermia was initiated within 6 hours of symptom onset by the emergency medical service with surface cooling pads and cold saline, and continued in the cath lab with endovascular cooling (target temperature: ≤35°C at time of reperfusion). Myocardial salvage index (using CMR) was compared in a randomised, controlled, open-label, endpoint blinded trial to a not-cooled group of patients at day 4±2 after the event. RESULTS: After postrandomisation exclusion of 19 patients a total of 101 patients were included in the intention-to-treat analysis (control group: n=54; hypothermia group: n=47). Target temperature was reached in 38/47 patients (81%) in the intervention group. Study-related interventions resulted in a delay in time from first medical contact to reperfusion of 14 min (control group 89±24 min; hypothermia group 103±21 min; p<0.01). Myocardial salvage index was 0.37 (±0.26) in the control group and 0.43 (±0.27) in the hypothermia group (p=0.27). No differences in cardiac biomarkers or clinical outcomes were found. In a CMR follow-up 6 months after the initial event no significant differences were detected. CONCLUSION: Out-of-hospital induced therapeutic hypothermia as an adjunct to primary percutaneous coronary intervention did not improve myocardial salvage in patients with STEMI. TRIAL REGISTRATION NUMBER: NCT01777750.

The impact of airway strategy on the patient outcome after out-of-hospital cardiac arrest: A propensity score matched analysis.

BACKGROUND: While guidelines mentioned supraglottic airway management in the case of out-of- hospital cardiac arrest, robust data of their impact on the patient outcome remain scare and results are inconclusive. METHODS: To assess the impact of the airway strategy on the patient outcome we prospectively enrolled 2224 individuals suffering cardiac arrest who were treated by the Viennese municipal emergency medical service. To control for potential confounders, propensity score matching was performed. Patients were matched in four groups with a 1:1:1:1 ratio ( n=210/group) according to bag-mask-valve, laryngeal tube, endotracheal intubation and secondary endotracheal intubation after primary laryngeal tube ventilation. RESULTS: The laryngeal tube subgroup showed the lowest 30-day survival rate among all tested devices ( p<0.001). However, in the case of endotracheal intubation after primary laryngeal tube ventilation, survival rates were comparable to the primary endotracheal tube subgroup. The use of a laryngeal tube was independently and directly associated with mortality with an adjusted odds ratio of 1.97 (confidence interval: 1.14-3.39; p=0.015). Additionally, patients receiving laryngeal tube ventilation showed the lowest rate of good neurological performance (6.7%; p<0.001) among subgroups. However, if patients received endotracheal intubation after initial laryngeal tube ventilation, the outcome proved to be significantly better (9.5%; p<0.001). CONCLUSION: We found that the use of a laryngeal tube for airway management in cardiac arrest was significantly associated with poor 30-day survival rates and unfavourable neurological outcome. A primary endotracheal airway management needs to be considered at the scene, or an earliest possible secondary endotracheal intubation during both pre-hospital and in-hospital post-return of spontaneous circulation critical care seems crucial and most beneficial for the patient outcome.

Continuous versus intermittent neuromuscular blockade in patients during targeted temperature management after resuscitation from cardiac arrest-A randomized, double blinded, double dummy, clinical trial.

AIM OF THE STUDY: Current guidelines recommend targeted temperature management to improve neurological outcome after cardiac arrest. Evidence regarding an ideal sedative/analgesic regimen including skeletal muscle paralysis is limited. METHODS: Patients were randomized to either a continuous administration of rocuronium (continuous-NMB-group) or to a continuous administration of saline supplemented by rocuronium bolus administration if demanded (bolus-NMB-group). The primary outcome was the number of shivering episodes. Secondary outcomes included survival and neurological status one year after cardiac arrest, time to awakening, length of stay as well as required cumulative dose of rocuronium, midazolam and fentanyl. RESULTS: Sixty-three patients (32 continuous-NMB-group; 31 bolus-NMB-group) were enrolled. Differences in baseline characteristics were not significant. Shivering episodes were detected in 94% of the patients in the bolus-NMB-group compared to 25% of the patients receiving continuous rocuronium infusion (p<0.01). The continuous-NMB-group received significant lower doses of midazolam (4.3±0.8mg/kg vs. 5.1±0.9mg/kg, p<0.01) and fentanyl (62±14µg/kg vs. 71±7µg/kg, p<0.01), but higher cumulative doses of rocuronium (7.8±1.8mg/kg vs. 2.3±1.6mg/kg, p<0.01). Earlier awakening (2 [IQR 2;3] vs. 4 [IQR 2;7.5] days, p=0.04) and decreased length of stay at the ICU (6 [IQR 3;5.9] vs. 10 [IQR 5;15] days, p=0.03) were observed in the continuous-NMB-group. There were no significant differences in survival and quality of life 12 months after cardiac arrest. CONCLUSIONS: Continuous neuromuscular blockade during the first day after resuscitation reduced shivering, midazolam and fentanyl requirement, time to awakening and discharge from intensive care unit. There were no differences in overall survival, cooling rate and time to target temperature.

Feasibility of profound hypothermia as part of extracorporeal life support in a pig model.

OBJECTIVE: To investigate the feasibility of a refined aortic flush catheter and pump system to induce emergency preservation and resuscitation before extracorporeal cardiopulmonary resuscitation in a normovolemic cardiac arrest swine model simulating near real size/weight conditions of adults. METHODS: In this feasibility study, 8 female Large White breed pigs weighing 70 to 80 kg underwent ventricular fibrillation cardiac arrest for 15 minutes, followed by 4°C aortic flush (150 mL/kg for the brain; 50 mL/kg for the spine) via a new hardware ensued by resuscitation with extracorporeal cardiopulmonary resuscitation. RESULTS: Brain temperature was lowered from 39.9°C (interquartile range [IQR] 39.6-40.3) to 24.0°C (IQR 20.8-28.9) in 12 minutes (IQR 11-16) with a median cooling rate of 1.3°C (IQR 0.7-1.6) per minute. A median of 776 mL (IQR 673-840) per minute with a median pump pressure of 1487 mm Hg (IQR 1324-1545) were pumped to the brain. CONCLUSIONS: With the new hardware, we were able to cool the brain within a few minutes in a large pig cardiac arrest model. The exact position; the design, diameter, and length of the flush catheter; and the brain perfusion pressure seem to be critical to effectively reduce brain temperature. Redistribution of peripheral blood could lead to sterile inflammation again and might be avoided.

Age-specific prognostication after out-of-hospital cardiac arrest - The ethical dilemma between 'life-sustaining treatment' and 'the right to die' in the elderly.

BACKGROUND: While prognostic values on survival after out-of-hospital cardiac arrest have been well investigated, less attention has been paid to their age-specific relevance. Therefore, we aimed to identify suitable age-specific early prognostication in elderly patients suffering out-of-hospital cardiac arrest in order to reduce the burden of unnecessary treatment and harm. METHODS: In a prospective population-based observational trial on individuals suffering out-of-hospital cardiac arrest, a total of 2223 patients receiving resuscitation attempts by the local emergency medical service in Vienna, Austria, were enrolled. Patients were stratified according to age as follows: young and middle-aged individuals (<65 years), young old individuals (65-74 years), old individuals (75-84 years) and very old individuals (>85 years). RESULTS: There was an increasing rate of 30-day mortality (+21.8%, p < 0.001) and unfavourable neurological outcome (+18.8%, p < 0.001) with increasing age among age groups. Established predictive variables lost their prognostic potential with increasing age, even after adjusting for potential confounders. Independently, an initially shockable electrocardiogram proved to be directly associated with survival, with an adjusted hazard ratio (HR) of 2.04 (95% confidence interval (CI) 1.89-2.38, p = 0.003) for >85-year-olds. Frailty was directly associated with mortality (HR 1.22, 95% CI 1.01-1.51, p = 0.049), showing a 30-day survival of 5.6% and a favourable neurological outcome of 1.1% among elderly individuals. CONCLUSION: An initially shockable electrocardiogram proved to be a suitable tool for risk assessment and decision making in order to predict a successful outcome in elderly victims of out-of-hospital cardiac arrest. However, the outcomes of elderly patients seemed to be exceptionally poor in frail individuals and need to be considered in order to reduce unnecessary treatment decisions.