[Hypothermic temperature control after successful resuscitation of out-of-hospital cardiac arrest in adults : Statement from the resuscitation and postresuscitation treatment working groups of the German Society of Medical Intensive Care and Emergency Medicine (DGIIN) and the German Interdisciplinary Association for Intensive Care and Emergency Medicine (DIVI), the German Society for Interdisciplinary Emergency and Acute Medicine (DGINA) and the Austrian Association of Emergency Medicine (AAEM)]. / Hypotherme Temperaturkontrolle nach erfolgreicher Wiederbelebung eines außerklinischen Herz-Kreislauf-Stillstands beim Erwachsenen : Statement der Arbeitsgruppen Reanimation und Post-Reanimationsbehandlung in der Deutschen Gesellschaft für Internistische Intensiv- und Notfallmedizin (DGIIN) und Deutschen Interdisziplinären Vereinigung für Intensiv- und Notfallmedizin (DIVI), der Deutschen Gesellschaft Interdisziplinäre Notfall- und Akutmedizin (DGINA) und der Österreichischen Gesellschaft für Notfallmedizin (AAEM).

In Germany per year approximately 60,000 and in Austria 5,000 adult patients suffer from out-of-hospital cardiac arrest. Only 10-15% of these patients survive without neurological damage. For decades hypothermic temperature control has been a central component of post-resuscitation treatment, but is controversial due to recently published studies.

Standard blood laboratory values as a clinical support tool to distinguish between SARS-CoV-2 positive and negative patients.

Standard blood laboratory parameters may have diagnostic potential, if polymerase-chain-reaction (PCR) tests are not available on time. We evaluated standard blood laboratory parameters of 655 COVID-19 patients suspected to be infected with SARS-CoV-2, who underwent PCR testing in one of five hospitals in Vienna, Austria. We compared laboratory parameters, clinical characteristics, and outcomes between positive and negative PCR-tested patients and evaluated the ability of those parameters to distinguish between groups. Of the 590 patients (20-100 years, 276 females and 314 males), 208 were PCR-positive. Positive compared to negative PCR-tested patients had significantly lower levels of leukocytes, neutrophils, basophils, eosinophils, lymphocytes, neutrophil-to-lymphocyte ratio, monocytes, and thrombocytes; while significantly higher levels were detected with erythrocytes, hemoglobin, hematocrit, C-reactive-protein, ferritin, activated-partial-thromboplastin-time, alanine-aminotransferase, aspartate-aminotransferase, lipase, creatine-kinase, and lactate-dehydrogenase. From all blood parameters, eosinophils, ferritin, leukocytes, and erythrocytes showed the highest ability to distinguish between COVID-19 positive and negative patients (area-under-curve, AUC: 72.3-79.4%). The AUC of our model was 0.915 (95% confidence intervals, 0.876-0.955). Leukopenia, eosinopenia, elevated erythrocytes, and hemoglobin were among the strongest markers regarding accuracy, sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio, and post-test probabilities. Our findings suggest that especially leukopenia, eosinopenia, and elevated hemoglobin are helpful to distinguish between COVID-19 positive and negative tested patients.

The capability of professional- and lay-rescuers to estimate the chest compression-depth target: a short, randomized experiment.

BACKGROUND: In CPR, sufficient compression depth is essential. The American Heart Association ("at least 5cm", AHA-R) and the European Resuscitation Council ("at least 5cm, but not to exceed 6cm", ERC-R) recommendations differ, and both are hardly achieved. This study aims to investigate the effects of differing target depth instructions on compression depth performances of professional and lay-rescuers. METHODS: 110 professional-rescuers and 110 lay-rescuers were randomized (1:1, 4 groups) to estimate the AHA-R or ERC-R on a paper sheet (given horizontal axis) using a pencil and to perform chest compressions according to AHA-R or ERC-R on a manikin. Distance estimation and compression depth were the outcome variables. RESULTS: Professional-rescuers estimated the distance according to AHA-R in 19/55 (34.5%) and to ERC-R in 20/55 (36.4%) cases (p=0.84). Professional-rescuers achieved correct compression depth according to AHA-R in 39/55 (70.9%) and to ERC-R in 36/55 (65.4%) cases (p=0.97). Lay-rescuers estimated the distance correctly according to AHA-R in 18/55 (32.7%) and to ERC-R in 20/55 (36.4%) cases (p=0.59). Lay-rescuers yielded correct compression depth according to AHA-R in 39/55 (70.9%) and to ERC-R in 26/55 (47.3%) cases (p=0.02). CONCLUSION: Professional and lay-rescuers have severe difficulties in correctly estimating distance on a sheet of paper. Professional-rescuers are able to yield AHA-R and ERC-R targets likewise. In lay-rescuers AHA-R was associated with significantly higher success rates. The inability to estimate distance could explain the failure to appropriately perform chest compressions. For teaching lay-rescuers, the AHA-R with no upper limit of compression depth might be preferable.

"Push as hard as you can" instruction for telephone cardiopulmonary resuscitation: a randomized simulation study.

BACKGROUND: The medical priority dispatch system (MPDS®) assists lay rescuers in protocol-driven telephone-assisted cardiopulmonary resuscitation (CPR). OBJECTIVE: Our aim was to clarify which CPR instruction leads to sufficient compression depth. METHODS: This was an investigator-blinded, randomized, parallel group, simulation study to investigate 10 min of chest compressions after the instruction "push down firmly 5 cm" vs. "push as hard as you can." Primary outcome was defined as compression depth. Secondary outcomes were participants exertion measured by Borg scale, provider's systolic and diastolic blood pressure, and quality values measured by the skill-reporting program of the Resusci(®) Anne Simulator manikin. For the analysis of the primary outcome, we used a linear random intercept model to allow for the repeated measurements with the intervention as a covariate. RESULTS: Thirteen participants were allocated to control and intervention. One participant (intervention) dropped out after min 7 because of exhaustion. Primary outcome showed a mean compression depth of 44.1 mm, with an inter-individual standard deviation (SDb) of 13.0 mm and an intra-individual standard deviation (SDw) of 6.7 mm for the control group vs. 46.1 mm and a SDb of 9.0 mm and SDw of 10.3 mm for the intervention group (difference: 1.9; 95% confidence interval -6.9 to 10.8; p = 0.66). Secondary outcomes showed no difference for exhaustion and CPR-quality values. CONCLUSIONS: There is no difference in compression depth, quality of CPR, or physical strain on lay rescuers using the initial instruction "push as hard as you can" vs. the standard MPDS(®) instruction "push down firmly 5 cm."

Performance of supraglottic airway devices and 12 month skill retention: a randomized controlled study with manikins.

PURPOSE: Airway management for successful ventilation by laypersons and inexperienced healthcare providers is difficult to achieve. Bag-valve mask (BVM) ventilation requires extensive training and is performed poorly. Supraglottic airway devices (SADs) have been successfully introduced to clinical resuscitation practice as an alternative. We evaluated recently introduced (i-gel™ and LMA-Supreme™) and established SADs (LMA-Unique™, LMA-ProSeal™) and BVM used by laypeople in training sessions on manikins. METHODS: In this randomized controlled study, 267 third-year medical students participated with informed consent and IRB approval. After brief standardized training, each participant applied all devices in a randomized order. Success of device application and ventilation was recorded. Without further training, skill retention was assessed in the same manner 12 months later. Outcome parameters were the number of application attempts, application time, tidal volume and gastric inflation rate recorded at successful attempts, and subjective ease-of-use rating by the participants. RESULTS: i-gel™ and LMA-Supreme™ were the most successful in the first attempt at both assessments and in the subjective ease-of-use rating. The shortest application time was found with BVM (8 ± 5s in 2008 vs. 9 ± 5s in 2009) and i-gel (10 ± 3s vs. 12 ± 5s). Tidal volumes were disappointing with no device reaching 50% volume within the recommended range (0.4-0.6L). Gastric inflation rate was highest with BVM (18% vs. 20%) but significantly lower with all SADs (0.4-6%; p < 0.001 for 2008 and 2009). CONCLUSION: SADs showed clear advantages over BVM. Compared with LMA-Unique™ and LMA-ProSeal™, i-gel™ and LMA-Supreme™ led to higher first-attempt success rates and a shorter application time.

The strong ion gap and outcome after cardiac arrest in patients treated with therapeutic hypothermia: a retrospective study.

OBJECTIVE: This study investigates whether the strong ion gap (SIG) is associated with long-term outcome after cardiac arrest in patients treated with therapeutic hypothermia. The hypothesis of the study was that an elevated SIG was associated with unfavourable outcome after cardiac arrest. DESIGN: Retrospective review of records from 1995 to 2007 of patients who received cardiopulmonary resuscitation. SETTING: Emergency department of a university hospital. PATIENTS: Patients who were successfully resuscitated after cardiac arrest (n = 288) and treated with mild therapeutic hypothermia. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Acid-base variables were calculated according to Stewart's approach, as modified by Figge and Fencl, and were determined immediately on admission and 12 h after the return of spontaneous circulation. Acid-base variables were determined at 37 degrees C and are reported without correction for patient temperature. Differences in SIG were compared between patients with favourable (survival 6 months with cerebral performance category 1 or 2) and unfavourable outcomes. SIG on admission and 12 h after return of spontaneous circulation was higher in patients with unfavourable outcome (n = 151; 52%). SIG 12 h after return of spontaneous circulation was identified as an independent predictor of outcome. A SIG > 8.9 mmol/L was associated with an increased cumulative hazard of death. CONCLUSIONS: An elevated SIG 12 h after return of spontaneous circulation may be associated with unfavourable outcome in patients after cardiac arrest treated with mild therapeutic hypothermia. The unmeasured anions hidden behind an elevated SIG may represent markers of tissue damage.

Results from Austria's nationwide public access defibrillation (ANPAD) programme collected over 2 years.

AIM OF THE STUDY: To analyse 2 years of experience after introducing automated external defibrillators (AED) all over Austria. MATERIALS AND METHODS: This observational study evaluated the number of privately purchased devices and the rate of local bystander-triggered AED deployments from November 2002 to December 2004. As outcome measurements, the hospital discharge rate and neurological condition were recorded. Arrival times of the emergency medical service (EMS) on scene and the time intervals until shock decisions were made were calculated. Shock decisions were verified according to ECG downloads. Results were compared with historical data if applicable. RESULTS: During the study period, 1865 devices were installed. Seventy-three AED deployments were recorded. Eleven cases were excluded from the study because bystanders were part of the local EMS. Seventeen out of the remaining 62 (27%) compared to a historical 27 out of 623 (4.3%) individuals were discharged alive from hospital. Fourteen out of 26 (54%) patients who were found with a shockable rhythm survived to hospital discharge. Fifteen of our patients survived in good neurological condition (CPC I and II), two suffered from severe neurological deficit (CPC III and IV) and 45 people died. The median "call-to-AED advice interval" was 3.5 min (IQR 2-6 min; N=24). In two cases, the AED made inappropriate decisions because of artefacts. CONCLUSIONS: Compared to historical data, short 'intervals to shock' delivery and the frequent start of basic life support resulted in an increased hospital discharge rate in good neurological condition. Despite the relatively high number of installed devices, the number of patients reached remained small.

Gas concentrations in expired air during basic life support using different ratios of compression to ventilation.

AIM: In cardiopulmonary resuscitation, different ratios of compression to ventilation with regard to optimal oxygen transport are considered. We hypothesised that the end tidal fraction of oxygen might increase from levels found in the conventional compression-ventilation ratio of 15:2 if more consecutive ventilations are given because the rescuer would hyperventilate. The second hypothesis was that the air blown into an infant with mouth to mouth ventilation consists of rescuer's dead space air only, meaning that the fraction of oxygen should increase. METHODS: In a basic life support simulation, we measured the expired air of rescuers using a VmaxST (Sensormedics, USA) respiratory gas analyser connected to an adult and to an infant resuscitation manikin. Fourteen participants performed five different compression-ventilation ratios (30:2, 30:5, 50:5, 100:10 and 5:1). These were compared to a ratio of 15:2 (control group). RESULTS: We found a significant increase in end tidal oxygen in 30:2 (16.3%), 30:5 (16.8%), 50:5 (16.8%), 100:10 (17.0%) compared to 15:2 (15.9%), p< or =0.004 for all groups versus control; p for trend: 0.014. In the infant CPR observation (ratio 5:1), the difference with the adult control group (15:2) also reached statistical significance (17.9% versus 15.9%, p=0.0005). CONCLUSION: Increasing consecutive compressions and ventilations above 15:2 leads to a statistically significant increase in expired fraction of oxygen. In infant ventilation, the air exhaled into a victim contains some dead space air with a higher end tidal oxygen fraction than in adults.

Quality of cardiopulmonary resuscitation among highly trained staff in an emergency department setting.

BACKGROUND: Recent reports have highlighted the poor standard of cardiopulmonary resuscitation (CPR) achieved by health care professionals in diverse situations. We explored what can be achieved in an emergency department by highly trained permanent staff. METHODS: In a prospective observational study conducted from June 1, 2002, to August 31, 2005, 80 of 213 patients requiring CPR and admitted to the emergency department of a tertiary care hospital were eligible for study participation. Owing to several logistic problems with CPR, 133 patients could not be studied. The CPR team consisted of emergency- and critical care-trained physicians with more than 10 years of acute care experience, most of whom were instructors of European Resuscitation Council courses in basic and advanced life support. A specially designed defibrillator was used to assess the quality of CPR. RESULTS: For 80 patients, 95 data sets were available for analysis, yielding a total of 1065 minutes of cardiac arrest time. Chest compressions were performed at a rate of 114 (95% confidence interval [CI], 112-116) per minute, resulting in a mean of 96 (95% CI, 93-99) delivered chest compressions per minute. We further observed a mean hands-off ratio of 12.7% (95% CI, 12.3%-13.1%), and the hands-off ratio was linearly associated with the duration of CPR (R(2) = 0.95; mean, 4.3% increments per 5-10 minutes; P<.001). Patients were hyperventilated with a median of 18 (interquartile range, 14-24) ventilations per minute. CONCLUSIONS: Highly trained professionals in an emergency department can achieve appropriate chest compression rates during CPR with a low hands-off ratio. Increased attention must be paid in all situations to the avoidance of hyperventilation.

Cardiac arrest in public locations--an independent predictor for better outcome?

OBJECTIVE: Outcome after cardiac arrest is known to be influenced by immediate access to resuscitation. We aimed to analyse the location of arrest in relation to the prognostic value for outcome. DESIGN: Retrospective review from prospective databases (ambulance routine documentation database and emergency department database on patients treated for cardiac arrest). SETTING: Vienna (1.7 million inhabitants) ambulance service and tertiary care facility (university clinics). PATIENTS: Two independent cohorts: (1) a population-based cohort of patients who were treated for cardiac arrest by the municipal ambulance service outside the hospital. The endpoint in this group was survival to hospital admission with spontaneous circulation. (2) A cohort of patients who were admitted to the emergency department after successful out of hospital resuscitation. The endpoint in this group was survival to 6 months with good neurological status (best Cerebral Performance Category 1 or 2 within 6 months). MEASUREMENTS: We analysed whether the location of non-traumatic adult out-of-hospital cardiac arrest (public versus private place) was a predictor for good outcome. RESULTS: PATIENTS who had cardiac arrest in a public location were more likely to arrive in hospital alive (39% versus 31%, crude OR 1.4, 95% CI 1.001-1.975, p=0.049) and were more likely to have a good neurological outcome after 6 months (35% versus 25%, crude OR 1.65, adjusted OR 1.59, 95% CI 1.07-2.36, p=0.023), compared to patients who had cardiac arrest in a non-public location. CONCLUSION: Cardiac arrest in a public location is independently associated with a better outcome.

CPR courses and semi-automatic defibrillators--life saving in cardiac arrest?

OBJECTIVES: The aim was to assess the knowledge of life-supporting first-aid in both cardiac arrest survivors and relatives, and their willingness to have a semi-automatic external defibrillator in their homes and use it in an emergency. MATERIAL AND METHODS: Cardiac arrest survivors, their families, friends, neighbours and co-workers were interviewed by medical students using prepared questionnaires. Their knowledge and self-assessment of life-supporting first-aid, their willingness to have a semi-automatic defibrillator in their homes and their willingness to use it in an emergency before and after a course in cardiopulmonary resuscitation (CPR) with a semi-automatic external defibrillator was evaluated. Courses were taught by medical students who had received special training in basic and advanced life support. RESULTS: Both patients and relatives, after a course of 2-3 h, were no longer afraid of making mistakes by providing life-supporting first-aid. The automated external defibrillator (AED) was generally accepted and considered easy to handle. CONCLUSION: We consider equipping high-risk patients and their families with AEDs as a viable method of increasing their survival in case of a recurring cardiac arrest. This, of course, should be corroborated by further studies.

Differing operational outcomes with six commercially available automated external defibrillators.

INTRODUCTION: In general automated external defibrillators (AED) are handled easily, but some untrained lay rescuers may have major problems with the use of such products. This may result in delayed shock delivery and delay in basic life support (BLS) after use of the AED. To study the effect of voice prompts and design solutions we tested the time from the first shock to the initiation of BLS for six defibrillators available in Austria. METHODS: Volunteers, who had no AED training, were evaluated to see when they delivered the first shock and how often BLS was started after the voice prompts were given by the defibrillators. RESULTS: Time to first shock delivered ranged from 78 (95% CI: 68-89) to 128 (95% CI: 110-146)s. The defibrillator-type had a significant influence on the time to first shock delivered (P < 0.0001). The proportion of volunteers who started BLS after defibrillation ranged from 93 to 33% and differed significantly between the AEDs used (P < 0.03). CONCLUSIONS: We demonstrated that there are significant differences between AEDs, concerning important operational outcomes like time to first shock and the start of BLS. Further research and development is urgently required to optimise user-friendliness and operational outcomes.

Hypothermia after cardiac arrest: a treatment that works.

PURPOSE OF REVIEW: Sudden death from cardiac arrest is a major health problem that still receives too little publicity. Current therapy after cardiac arrest concentrates on resuscitation efforts because, until now, no specific therapy for brain protection after restoration of spontaneous circulation was available. Therapeutic mild or moderate resuscitative hypothermia is a novel therapy with multifaceted chemical and physical effects by preventing or mitigating the derangements seen in the postresuscitation syndrome. RECENT FINDINGS AND SUMMARY: In 2002, two prospective, randomized studies reported improved outcomes when deliberate hypothermia was induced in comatose survivors after resuscitation from cardiac arrest. However, several issues with regard to resuscitative cooling are still unanswered and should be studied further. These include the optimal timing to initiate cooling, the optimal cooling period, the optimal temperature level, and rewarming strategy. Even important questions, such as which cooling technique will be available in the near future that would combine ease of use with high efficacy, are not answered yet.

Lunar phases are not related to the occurrence of acute myocardial infarction and sudden cardiac death.

BACKGROUND: Mass media deliver pertinacious rumours that lunar phases influence the progress and long-term results in several medical procedures. Peer reviewed studies support this, e.g. in myocardial infarction, others do not. METHODS: We looked retrospectively at the dates of cardiac arrests (CA; n=368) of cardiac origin and of acute myocardial infarctions (AMI) with consecutive thrombolytic therapy or acute PTCA (n=872) and at the lunar phases at the corresponding dates. Medical data had been collected prospectively on the patient's admission. The lunar phases were defined as full moon+/-1 day, new moon+/-1 day and the days in between as waning and waxing moon. The incidence of these cardiac events at each phase was calculated as days with a case divided by the total number of days of the specific moon phase in the observation period (1992-1998). Wilcoxon Rank Test was used for statistical analysis. RESULTS: AMI and CA occurred on equal percentages of days within each lunar phase: AMI on 35% of all days with new moon, on 38% of full moon days, on 39% waning, and on 41% of the waxing moon days; CA on 19, 17, 16 and 16% of all days of the respective lunar phase. This difference was not significant. CONCLUSION: Lunar phases do not appear to correlate with acute coronary events leading to myocardial infarction or sudden cardiac death.

Endothelin-1 elevates regional cerebral perfusion during prolonged ventricular fibrillation cardiac arrest in pigs.

Since adrenaline (epinephrine) also has negative effects during and after cardiopulmonary resuscitation (CPR) a non-adrenergic vasoconstrictor like endothelin might be an alternative to increase vital organ blood flow. We studied the effect of different doses of endothelin-1 compared with adrenaline on the ability to resuscitate, cerebral and myocardial blood flow (MBF) in a closed chest cardiac arrest pig model. After 5 min of ventricular fibrillation, CPR with a ventilator and a mechanical compression device was started. At 10 min, 31 pigs were randomized to receive a single dose of endothelin-1 50, 100 or 200 microg or repeated doses of adrenaline 0.04 mg kg(-1) or saline every 3 min. After 25 min, the pigs were defibrillated to achieve restoration of spontaneous circulation. Blood flow was measured with the fluorescent microsphere method. In animals receiving endothelin-1 50, 100 and 200 microg the cerebral blood flow (CBF) increased from median 28 (25th; 75th quartile: 16; 40), 32 (15; 48) and 17 (4; 65) to 36 (31; 54), 47 (39; 57) and 63 (35; 83) ml min(-1) per 100 g, respectively, 6 min after drug administration (P<0.05 endothelin-1 50 microg vs. Control, P<0.01 endothelin-1 100 and 200 microg vs. Control). At the same time CBF decreased in the control and adrenaline group from 36 (21; 41) and 39 (15; 50) to 12 (2; 25) and 24 (15; 26) ml min(-1) per 100 g, respectively, (P<0.05 adrenaline vs. endothelin-1 200 microg). There was no difference in MBF between the treatment groups despite a higher coronary perfusion pressure (CoPP) in the endothelin-1 groups. Restoration of spontaneous circulation could be only achieved in the endothelin-1 50 microg (3 of 7; 43%) and 100 microg (5 of 7; 71%) group. This study suggests that endothelin-1 enhances CBF during CPR better than adrenaline and increases resuscitation success.

Survivors of ventricular tachyarrhythmias due to a transient or reversible disorder have a high recurrence rate of lethal cardiac events.

OBJECTIVES: The recurrence rate of lethal cardiac events after the survival of a primary cardiac arrest in patients not having received an implantable cardioverter defibrillator (ICD) is investigated. BACKGROUND: According to current guidelines, only a small percentage of patients after successful cardiopulmonary resuscitation due to an underlying cardiac problem are eligible for the implantation of an ICD. METHODS: For retrospective analysis, we used a data registry of patients admitted to an emergency department after cardiac arrest. Patients who had a primary cardiac cause for their cardiac arrest and who did not die within the first month after successful restoration of spontaneous circulation were selected. RESULTS: From 1246 patients, 360 met the inclusion criteria. A second lethal cardiac event occurred in 94 (26%). Of those 94 patients, 57 (61%) had good neurological function before their second cardiac arrest. Of the survivors with good neurological function, 47 (82%) did not have an ICD or a cardiac transplant. Another cardiac arrest due to a primary cardiac event occurred in 34 (72%) of these patients. CONCLUSIONS: Cardiac arrest survivors without an apparent indication for an ICD have a high risk of suffering from a re-arrest of cardiac origin.

Dashing with scooters to in-hospital emergencies: a randomised cross-over experiment.

OBJECTIVE: Physical exhaustion is a frequent condition in emergency medical teams after in-house emergency runs, which might affect the quality of advanced care. Newly available light-weight scooters may reduce exertion as measured by the cardiovascular response in these circumstances and, therefore, may reduce physical exhaustion on arrival. METHODS: We undertook a randomised cross-over trial in a simulated in-house emergency alarm run to examine the influence of scooting compared with conventional running on pulse rate (primary outcome), manual skillfulness and response time. RESULTS: We tested 24 emergency department professionals in eight emergency medical teams. After scooting the pulse rate was significantly lower compared with conventional running [157 (IQR 145-169) vs. 170 (IQR 154-175) min(-1), P=0.004]. After the simulated emergency alarm run no difference was found in manual skillfulness and response time between scooting and running. CONCLUSION: Using scooters for simulated in-house emergency alarm runs markedly reduces the cardiovascular response of emergency medical teams.