Roman-Patrik Lukas

Chest compression quality management and return of spontaneous circulation: A matched-pair registry study

AIMS Investigating the effects of any intervention during cardiac arrest remains difficult. The ROSC after cardiac arrest score was introduced to facilitate comparison of rates of return of spontaneous circulation (ROSC) between different ambulance services. To study the influence of chest compression quality management (including training, real-time feedback devices, and debriefing) in comparison with conventional cardiopulmonary resuscitation (CPR), a matched-pair analysis was conducted using data from the German Resuscitation Registry, with the calculated ROSC after cardiac arrest score as the baseline. METHODS AND RESULTS Matching for independent ROSC after cardiac arrest score variables yielded 319 matched cases from the study period (January 2007-March 2011). The score predicted a 45% ROSC rate for the matched pairs. The observed ROSC increased significantly with chest compression quality management, to 52% (P=0.013; 95% CI, 46-57%). No significant differences were seen in the conventional CPR group (47%; 95% CI, 42-53%). The difference between the observed ROSC rates was not statistically significant. CONCLUSIONS Chest compression quality management leads to significantly higher ROSC rates than those predicted by the prognostic score (ROSC after cardiac arrest score). Matched-pair analysis shows that with conventional CPR, the observed ROSC rate was not significantly different from the predicted rate. Analysis shows a trend toward a higher ROSC rate for chest compression quality management in comparison with conventional CPR. It is unclear whether a single aspect of chest compression quality management or the combination of training, real-time feedback, and debriefing contributed to this result.

[Chest compression quality : Can feedback technology help?].

BACKGROUND The outcome of cardiopulmonary resuscitation (CPR) depends on the quality of chest compressions. Current European Resuscitation Council (ERC) guidelines promote the development of feedback systems. However, no studies presenting satisfactory results of feedback use have been published. METHODS A total of 60 patients with cardiac arrest (> or =18 years of age) received resuscitation attempts using an automated external defibrillator (AED) with real-time feedback by the ambulance service of the City of Münster. The frequency of chest compressions, no-flow time (NFT) and depth of chest compressions were analyzed for the first three cycles of CPR and compared to the ERC guidelines 2005. RESULTS Chest compression frequency did not differ significantly from the ideal as set out in the guidelines. Analysis of NFTs showed significantly longer NFT for the first cycle but NFT for the second and third cycles did not differ significantly from the ideal. The target depth of 4-5 cm was achieved in 80% of all chest compressions in the first 3 cycles. CONCLUSION With the AED real-time feedback technology used in this study standardized performance of chest compressions could be maintained in a professional ambulance service. Implementation of a feedback system requires training of ambulance staff.

Echtzeit-Feedback-Systeme zur Verbesserung der Reanimationsqualität

The quality of chest compression is a determinant of survival after cardiac arrest. Therefore, the European Resuscitation Council (ERC) 2010 guidelines on resuscitation strongly focus on compression quality. Despite its impact on survival, observational studies have shown that chest compression quality is not reached by professional rescue teams. Real-time feedback devices for resuscitation are able to measure chest compression during an ongoing resuscitation attempt through a sternal sensor equipped with a motion and pressure detection system. In addition to the electrocardiograph (ECG) ventilation can be detected by transthoracic impedance monitoring. In cases of quality deviation, such as shallow chest compression depth or hyperventilation, feedback systems produce visual or acoustic alarms. Rescuers can thereby be supported and guided to the requested quality in chest compression and ventilation. Feedback technology is currently available both as a so-called stand-alone device and as an integrated feature in a monitor/defibrillator unit. Multiple studies have demonstrated sustainable enhancement in the education of resuscitation due to the use of real-time feedback technology. There is evidence that real-time feedback for resuscitation combined with training and debriefing strategies can improve both resuscitation quality and patient survival. Chest compression quality is an independent predictor for survival in resuscitation and should therefore be measured and documented in further clinical multicenter trials.

Beeinflussen soziodemografische Faktoren Notarzteinsätze

BACKGROUND Demographic development and changes in healthcare utilization have led to a rising number of calls for emergency services. In Germany life-threatening situations are responded by physician-staffed ambulances in a 2-tier system whereas paramedic-staffed ambulances are dispatched in non-life-threatening emergencies. A nationwide protocol guides dispatchers in triage decisions. In the years 1999 to 2009 a continuous rise in the number of calls for a physician-staffed ambulance in Münster was recorded. The degree of healthcare utilization according to socioeconomic status and age structure was retrospectively examined. METHODS For the year 2006 all emergency calls in the City of Münster responded to by physician-staffed ambulances were analyzed. Each call was assigned to 1 of the 45 urban districts. The local incidence of emergency calls (calls/100 residents/year) was determined and compared to the socioeconomic status which was defined as the percentage of welfare and unemployment benefit recipients per district. Patient condition was assessed by the Munich National Advisory Committee for Aeronautics (M-NACA) score. This scoring system allows calls to be allocated to either life-threatening conditions or non-life-threatening conditions by objective vital parameters. The age structure of the emergency callers was also examined. RESULTS Urban districts with a low socioeconomic status showed a higher incidence of emergency calls requiring physician-staffed ambulance responses than districts with a high socioeconomic status. Measured by the M-NACA scoring system, the fraction of life-threatening emergencies among all calls proved to be equal to districts with a high socioeconomic status. A correlation between elderly patients and increasing numbers of life-threatening emergencies was found. CONCLUSIONS A low socioeconomic status of an urban district will result in more ambulance responses. However, the proportion of life-threatening emergencies is equal to districts with a high socioeconomic status. Thus, the greater need for physician-staffed ambulance responses matches clinical needs and legitimates current resource use in a 2-tier ambulance system. Indications for the abuse of physician-staffed ambulances were not found. Considering an aging population the number of emergency calls will rise in the future.

Laienreanimation – Reanimation als Schulfach: „Was Hänschen nicht lernt …“

Sudden cardiac arrest is a major contributor to avoidable deaths in Europe. Immediate start of basic life support (BLS) by laypersons is among the most successful strategies in the treatment of cardiac arrest patients. Despite the fact that more than half of all cardiac arrests in Germany are witnessed by a bystander, only in one fifth of all arrests layperson resuscitation is initiated. One strategy to enhance bystander BLS is to establish cardiac resuscitation tuition in schools. BLS instructions for pupils have been proven to be successfully implemented independent from childrens age or physical ability. Although an age-adjusted curriculum seems reasonable even usage of automatic external defibrillators (AED) can be taught effectually. The earlier in the life of a student BLS-instruction begins, the more successful the training is. However a national German curriculum for BLS-training in schools has yet to be established in Germany.

Predicting ROSC in out-of-hospital cardiac arrest using expiratory carbon dioxide concentration: Is trend-detection instead of absolute threshold values the key?

AIM Guidelines recommend detecting return of spontaneous circulation (ROSC) by a rising concentration of carbon dioxide in the exhalation air. As CO2 is influenced by numerous factors, no absolute cut-off values of CO2 to detect ROSC are agreed on so far. As trends in CO2 might be less affected by influencing factors, we investigated an approach which is based on detecting CO2-trends in real-time. METHODS We conducted a retrospective case-control study on 169 CO2 time series from out of hospital cardiac arrests resuscitated by Muenster City Ambulance-Service, Germany. A recently developed statistical method for real-time trend-detection (SCARM) was applied to each time series. For each series, the percentage of time points with detected positive and negative trends was determined. RESULTS ROSC time series had larger percentages of positive trends than No-ROSC time series (p=0.003). The median percentage of positive trends was 15% in the ROSC time series (IQR: 5% to 23%) and 7% in the No-ROSC time series (IQR: 3% to 14%). A receiver operating characteristic (ROC) analysis yielded an optimal threshold of 13% to differentiate between ROSC and No-ROSC cases with a specificity of 58.4% and sensitivity of 73.9%; the area under the curve was 63.5%. CONCLUSION Patients with ROSC differed from patients without ROSC as to the percentage of detected CO2 trends, indicating the potential of our real-time trend-detection approach. Since the study was designed as a proof of principle and its calculated specificity and sensitivity are low, more research is required to implement CO2-trend-detection into clinical use.

Echtzeit-Feedback-Systeme zur Verbesserung der Reanimationsqualität@@@Real-time feedback systems for improvement of resuscitation quality

The quality of chest compression is a determinant of survival after cardiac arrest. Therefore, the European Resuscitation Council (ERC) 2010 guidelines on resuscitation strongly focus on compression quality. Despite its impact on survival, observational studies have shown that chest compression quality is not reached by professional rescue teams. Real-time feedback devices for resuscitation are able to measure chest compression during an ongoing resuscitation attempt through a sternal sensor equipped with a motion and pressure detection system. In addition to the electrocardiograph (ECG) ventilation can be detected by transthoracic impedance monitoring. In cases of quality deviation, such as shallow chest compression depth or hyperventilation, feedback systems produce visual or acoustic alarms. Rescuers can thereby be supported and guided to the requested quality in chest compression and ventilation. Feedback technology is currently available both as a so-called stand-alone device and as an integrated feature in a monitor/defibrillator unit. Multiple studies have demonstrated sustainable enhancement in the education of resuscitation due to the use of real-time feedback technology. There is evidence that real-time feedback for resuscitation combined with training and debriefing strategies can improve both resuscitation quality and patient survival. Chest compression quality is an independent predictor for survival in resuscitation and should therefore be measured and documented in further clinical multicenter trials.

Beeinflussen soziodemografische Faktoren Notarzteinsätze?@@@Do sociodemographic factors influence emergency medical missions?: Analyse in der Stadt Münster@@@Analysis in the City of Münster

BACKGROUND Demographic development and changes in healthcare utilization have led to a rising number of calls for emergency services. In Germany life-threatening situations are responded by physician-staffed ambulances in a 2-tier system whereas paramedic-staffed ambulances are dispatched in non-life-threatening emergencies. A nationwide protocol guides dispatchers in triage decisions. In the years 1999 to 2009 a continuous rise in the number of calls for a physician-staffed ambulance in Münster was recorded. The degree of healthcare utilization according to socioeconomic status and age structure was retrospectively examined. METHODS For the year 2006 all emergency calls in the City of Münster responded to by physician-staffed ambulances were analyzed. Each call was assigned to 1 of the 45 urban districts. The local incidence of emergency calls (calls/100 residents/year) was determined and compared to the socioeconomic status which was defined as the percentage of welfare and unemployment benefit recipients per district. Patient condition was assessed by the Munich National Advisory Committee for Aeronautics (M-NACA) score. This scoring system allows calls to be allocated to either life-threatening conditions or non-life-threatening conditions by objective vital parameters. The age structure of the emergency callers was also examined. RESULTS Urban districts with a low socioeconomic status showed a higher incidence of emergency calls requiring physician-staffed ambulance responses than districts with a high socioeconomic status. Measured by the M-NACA scoring system, the fraction of life-threatening emergencies among all calls proved to be equal to districts with a high socioeconomic status. A correlation between elderly patients and increasing numbers of life-threatening emergencies was found. CONCLUSIONS A low socioeconomic status of an urban district will result in more ambulance responses. However, the proportion of life-threatening emergencies is equal to districts with a high socioeconomic status. Thus, the greater need for physician-staffed ambulance responses matches clinical needs and legitimates current resource use in a 2-tier ambulance system. Indications for the abuse of physician-staffed ambulances were not found. Considering an aging population the number of emergency calls will rise in the future.