Biomedical subjects

Anton N Laggner

Publications and source records attributed to Anton N Laggner.

At least 19 recordsLinked to original sources

PubMed2006

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.

Aged↗

PubMed2006

High acceptance of a home AED programme by survivors of sudden cardiac arrest and their families.

PURPOSE: The feasibility and acceptance of providing sudden cardiac arrest survivors with life supporting first aid training and automated external defibrillators (AEDs) at their homes is unknown. Preliminary experiences are reported here. METHODS: Trained medical students provided life supporting first aid courses including AED training to cardiac arrest survivors. Patients were asked to invite relatives and friends to such training sessions at their home. Laerdal Little Anne and Heartstart AED Trainer were used. An AED was placed at the patients' disposal. A refresher course took place 1 year later. Questionnaires were used to evaluate the project. RESULTS: Since 1999, 88 families have been trained and provided with an AED. Immediately after the training 90% (66% "agree", 24% "maybe yes") believed they would perform first aid correctly, 1 year later 98% did so (68% "agree", 29% "maybe yes") (p=0.03). Families considered feeling much safer having an AED at home. The handling of an AED was regarded to be easy and AEDs would even be used on strangers. Only on one occasion an AED was used in a real emergency situation. CONCLUSION: Providing patients and relatives with life support first aid and AED training at their homes is feasible and has raised no major objections by the family members. All have considered handling of an AED much simpler than providing basic life support and therefore none think that it would be a major problem to use it in case of an emergency. This still has to be proven.

Adult↗

PubMed2006

Efficacy and safety of endovascular cooling after cardiac arrest: cohort study and Bayesian approach.

BACKGROUND AND PURPOSE: Recently 2 randomized trials in comatose survivors of cardiac arrest documented that therapeutic hypothermia improved neurological recovery. The narrow inclusion criteria resulted in an international recommendation to cool only a restricted group of primary cardiac arrest survivors. In this retrospective cohort study we investigated the efficacy and safety of endovascular cooling in unselected survivors of cardiac arrest. METHODS: Consecutive comatose survivors of cardiac arrest, who were either cooled for 24 hours to 33 degrees C with endovascular cooling or treated with standard postresuscitation therapy, were analyzed. Complication data were obtained by retrospective chart review. RESULTS: Patients in the endovascular cooling group had 2-fold increased odds of survival (67/97 patients versus 466/941 patients; odds ratio 2.28, 95% CI, 1.45 to 3.57; P<0.001). After adjustment for baseline imbalances the odds ratio was 1.96 (95% CI, 1.19 to 3.23; P=0.008). When discounting the observational data in a Bayesian analysis by using a sceptical prior the posterior odds ratio was 1.61 (95% credible interval, 1.06 to 2.44). In the endovascular cooling group, 51/97 patients (53%) survived with favorable neurology as compared with 320/941 (34%) in the control group (odds ratio 2.15, 95% CI, 1.38 to 3.35; P=0.0003; adjusted odds ratio 2.56, 1.57 to 4.17). There was no difference in the rate of complications except for bradycardia. CONCLUSIONS: Endovascular cooling improved survival and short-term neurological recovery compared with standard treatment in comatose adult survivors of cardiac arrest. Temperature control was effective and safe with this device.

Aged↗

PubMed2006

Implementation of guidelines improves the standard of care: the Viennese registry on reperfusion strategies in ST-elevation myocardial infarction (Vienna STEMI registry).

BACKGROUND: The purpose of this study was to determine whether implementation of recent guidelines improves in-hospital mortality from acute ST-elevation myocardial infarction (STEMI) in a metropolitan area. METHODS AND RESULTS: We organized a network that consisted of the Viennese Ambulance Systems, which is responsible for diagnosis and triage of patients with acute STEMI, and 5 high-volume interventional cardiology departments to expand the performance of primary percutaneous catheter intervention (PPCI) and to use the fastest available reperfusion strategy in STEMI of short duration (2 to 3 hours from onset of symptoms), either PPCI or thrombolytic therapy (TT; prehospital or in-hospital), respectively. Implementation of guidelines resulted in increased numbers of patients receiving 1 of the 2 reperfusion strategies (from 66% to 86.6%). Accordingly, the proportion of patients not receiving reperfusion therapy dropped from 34% to 13.4%, respectively. PPCI usage increased from 16% to almost 60%, whereas the use of TT decreased from 50.5% to 26.7% in the participating centers. As a consequence, in-hospital mortality decreased from 16% before establishment of the network to 9.5%, including patients not receiving reperfusion therapy. Whereas PPCI and TT demonstrated comparable in-hospital mortality rates when initiated within 2 to 3 hours from onset of symptoms, PPCI was more effective in acute STEMI of >3 but <12 hours' duration. CONCLUSIONS: Implementation of recent guidelines for the treatment of acute STEMI by the organization of a cooperating network within a large metropolitan area was associated with a significant improvement in clinical outcomes.

Aged↗

PubMed2006

CPR in medical schools: learning by teaching BLS to sudden cardiac death survivors--a promising strategy for medical students?

BACKGROUND: Cardiopulmonary resuscitation (CPR) training is gaining more importance for medical students. There were many attempts to improve the basic life support (BLS) skills in medical students, some being rather successful, some less. We developed a new problem based learning curriculum, where students had to teach CPR to cardiac arrest survivors in order to improve the knowledge about life support skills of trainers and trainees. METHODS: Medical students who enrolled in our curriculum had to pass a 2 semester problem based learning session about the principles of cardiac arrest, CPR, BLS and defibrillation (CPR-D). Then the students taught cardiac arrest survivors who were randomly chosen out of a cardiac arrest database of our emergency department. Both, the student and the Sudden Cardiac Death (SCD) survivor were asked about their skills and knowledge via questionnaires immediately after the course. The questionnaires were then used to evaluate if this new teaching strategy is useful for learning CPR via a problem-based-learning course. The survey was grouped into three categories, namely "Use of AED", "CPR-D" and "Training". In addition, there was space for free answers where the participants could state their opinion in their own words, which provided some useful hints for upcoming programs. RESULTS: This new learning-by-teaching strategy was highly accepted by all participants, the students and the SCD survivors. Most SCD survivors would use their skills in case one of their relatives goes into cardiac arrest (96%). Furthermore, 86% of the trainees were able to deal with failures and/or disturbances by themselves. On the trainer's side, 96% of the students felt to be well prepared for the course and were considered to be competent by 96% of their trainees. CONCLUSION: We could prove that learning by teaching CPR is possible and is highly accepted by the students. By offering a compelling appreciation of what CPR can achieve in using survivors from SCD as trainees made them go deeper into the subject of resuscitation, what also might result in a longer lasting benefit than regular lecture courses in CPR.

Adult↗

PubMed2006

Rapid induction of cerebral hypothermia by aortic flush during normovolemic cardiac arrest in pigs.

OBJECTIVE: Induction of deep cerebral hypothermia before reperfusion might improve neurologic outcome after cardiac arrest. We hypothesized that an aortic flush with cold saline during cardiac arrest is able to induce deep cerebral hypothermia and that the cooling efficiency can be enhanced by a) increasing the arteriovenous pressure gradient during the flush with vasopressin; b) improving the cerebral microcirculation during the flush with the thrombolytic agent alteplase; and c) increasing the arteriovenous pressure gradient further with venting the right heart by draining blood during the flush. DESIGN: Prospective randomized experimental study. SETTING: University research laboratory. SUBJECTS: Twenty-four pigs Large White breed (31-42 kg). INTERVENTIONS: After 10 mins of ventricular fibrillation, pigs received an aortic flush (100 mL/kg, 4 degrees C, flow rate 35 mL/kg/min) into the descending aorta via a balloon catheter. The animals were subjected randomly to either an aortic flush with saline, saline plus vasopressin 1.2 IU/kg, saline plus alteplase 1 mg/kg, saline plus a combination of vasopressin 1.2 IU/kg and alteplase 1 mg/kg, or saline plus vasopressin 1.2 IU/kg and venting the right heart. Arterial and venous pressures and brain temperatures were recorded for an observation time of 10 mins after flush. MEASUREMENTS AND MAIN RESULTS: A sufficient arteriovenous pressure gradient and deep cerebral hypothermia were only achieved with a flush containing vasopressin (brain temperature 16.1+/-1.3 degrees C in the vasopressin group vs. 35.4+/-1.5 degrees C in the saline group, p<.001); combining vasopressin with alteplase, or venting the right heart, did not further enhance the cooling efficiency of the flush. CONCLUSIONS: A cold saline aortic flush with vasopressin rapidly decreases brain temperature during prolonged normovolemic cardiac arrest in pigs. Whether deep cerebral hypothermia induced before reperfusion can improve neurologic outcome after cardiac arrest needs further investigation in large animal outcome studies.

Animals↗

PubMed2006

Thoracic impedance changes measured via defibrillator pads can monitor ventilation in critically ill patients and during cardiopulmonary resuscitation.

OBJECTIVE: Monitoring of ventilation performance during cardiopulmonary resuscitation would be desirable to improve the quality of cardiopulmonary resuscitation. To investigate the potential for measuring ventilation rate and inspiration time, we calculated the correlation in waveform between transthoracic impedance measured via defibrillator pads and tidal volume given by a ventilator. DESIGN: Clinical study. SETTING: Emergency department of a tertiary care university hospital. PATIENTS: A convenience sample of mechanical ventilated patients (n = 32), cardiac arrest patients (n = 20), and patients after restoration of spontaneous circulation (n = 31) older than 18 were eligible. INTERVENTIONS: The Heartstart 4000SP defibrillator (Laerdal Medical Cooperation, Stavanger, Norway) with additional capabilities of recording thoracic impedance changes was used. MEASUREMENTS AND MAIN RESULTS: The relationship between impedance change and tidal volume (impedance coefficient) was calculated. The mean (sd) correlations between the impedance waveform and the tidal volume waveform in the patient groups studied were .971 (.027), .969 (.032), and .967 (.035), respectively. The mean (sd) impedance coefficient for all patients in the study was .00194 (.0078) Omega/mL, and the mean (sd) specific (weight-corrected) impedance coefficient was .152 (.048) Omega/kg/mL. The measured thorax impedance change for different tidal volumes (400-1000 mL) was approximately linear. CONCLUSIONS: The impedance sensor of a defibrillator is accurate in identifying tidal volumes, when chest compressions are interrupted. This also allows quantifying ventilation rates and inspiration times. However this technology, at its present state, provides only limited practical means for exact tidal volume estimation.

Adult↗

PubMed2006

Gender modifies the influence of age on outcome after successfully resuscitated cardiac arrest: a retrospective cohort study.

Age is an important risk factor for mortality and unfavorable outcome after successfully resuscitated cardiac arrest. Other risk factors may interact with this relationship. We conducted the current study to quantify the influence of age on mortality and unfavorable neurologic outcome of patients surviving out-of-hospital cardiac arrest, and to determine the role of other confounding variables. This study was based on a cardiac arrest registry comprising all patients with witnessed out-of-hospital cardiac arrest of cardiac origin after successful resuscitation admitted to a department of emergency medicine between September 1991 and December 2004. We assessed the association between age and mortality and the degree of neurologic impairment, adjusting for multiple risk factors. We tested for interaction between age and all other risk factors with outcome. With each year of age the adjusted odds ratio for in-hospital death increased by 1.05 (95% confidence interval [CI], 1.04-1.07), and the adjusted odds ratio for an unfavorable neurologic outcome increased by 1.04 (95% CI, 1.03-1.06). Interaction between age and sex was present, and the analysis was stratified to sex. For men we found a steep risk increase for death and unfavorable outcome after being resuscitated from cardiac arrest, with the highest risk in the oldest age quartile. For women we observed only a slight risk increase for death and almost no risk increase for unfavorable outcome. Age is a strong independent risk factor for mortality and neurologic impairment after successfully resuscitated cardiac arrest. The risk increase with advancing age is much greater in men than in women. Therefore, in women, the influence of age on prognosis after cardiac arrest may not be very important, while in men it still plays an important role. This should be considered especially when treating successfully resuscitated women and discussing the prognosis with the medical team or the patient's family.

Adult↗

PubMed2005

Preoperative antithrombin III activity predicts outcome after surgical repair of acute type A aortic dissection.

BACKGROUND: Acute Stanford type A aortic dissection is associated with substantial perioperative morbidity and mortality. A sepsis-like state may lead to antithrombin (AT) III consumption and deficiency. The impact of preoperative AT III activity on outcome in patients undergoing emergency surgery is yet unknown. METHODS: We measured preoperative AT III activity in 99 consecutive patients undergoing emergency aortic surgery for Stanford type A aortic dissection during a 4-year period in a retrospective study. Cardiovascular co-morbidities, risk factors and surgical data were recorded and patients were followed for 30-day mortality, and occurrence of multiple organ failure (MOF). RESULTS: During the first 30 days, 15 patients (15%) died, and 8 patients (8%) had MOF. Median AT III levels (IQR) in 30-day non-survivors versus survivors were 64% (52-72) versus 90% (75-97) (p<0.001), and in patients with versus without MOF were 66% (52.3-77.3) versus 88% (72-96) (p=0.018), respectively. Adjusted odds ratios for 30-day mortality and MOF for AT III activity (per % increments) were 0.92 (p=0.007), and 0.96 (p=0.012), respectively, indicating a significant inverse relationship between AT III activity and outcome. CONCLUSION: There is a strong inverse association between preoperative AT III activity and adverse outcome in patients undergoing surgical repair of acute Stanford type A aortic dissection. Larger studies are necessary to determine a cut-off value for AT III and to assess whether patients with low AT III levels benefit targeted therapeutic interventions.

Adult↗

PubMed2005

Extracorporeal venovenous cooling for induction of mild hypothermia in human-sized swine.

OBJECTIVE: Several cooling methods have been investigated for inducing mild hypothermia (33-36 degrees C) after cardiac arrest, brain trauma, or stroke. To achieve its best effect, therapeutic hypothermia has to be applied very early after the ischemic insult; otherwise, the beneficial effect would be diminished or even abrogated. The aim of this study was to investigate the effectiveness and safety of extracorporeal venovenous cooling as compared with endovascular cooling. DESIGN: Swine were cooled in a randomized crossover design from 38 degrees C to 33 degrees C brain temperature, either with extracorporeal venovenous cooling or with endovascular cooling. SETTING: Laboratory investigation. SUBJECTS: Six swine of human size (85 to 101 kg). INTERVENTIONS: Swine were randomly cooled with the first device, and after achieving the target brain temperature, re-warmed via the same technique and with heating lamps to baseline temperature. Then the other catheter was inserted and cooling was performed with the second device. MEASUREMENTS: Brain, pulmonary artery and tympanic temperature, blood pressure, and heart rate were recorded continuously. Laboratory samples, including free hemoglobin, were taken at predefined temperature points during cooling. Comparisons between and within (baseline vs. 33 degrees C) the treatment groups were performed with the paired Student's t-test. MAIN RESULTS: The time needed to reduce brain temperature from 38.0 degrees C to 33.0 degrees C was 41 +/- 17 mins with venovenous cooling and 126 +/- 37 mins with endovascular cooling (p = .001). Heart rate and mean arterial pressure decreased moderately during cooling and were significantly lower at 33 degrees C than at baseline in both groups, without differences between groups. None of the swine developed significant hemolysis, arrhythmias, or bleeding. CONCLUSIONS: Extracorporeal venovenous cooling was an effective and safe method to rapidly induce therapeutic mild hypothermia in human-sized swine. It seems to be promising for further application and investigation in patients.

Animals↗

PubMed2004

[Surgical reduction of fat surplus leading to pulmonary embolism].

Surgical reduction of fat surplus is usually performed on healthy individuals and is reported as a safe procedure as it is not associated with a lethal outcome. Due to the anticipation of peri- and postoperative bleeding as a result of the large wound area, which may have a negative influence on the cosmetic result, patients often receive no or only inadequate anticoagulation. We report three cases in which surgical reduction of fat surplus led to sudden collapse and cardiac arrest. In all of our patients, fatal pulmonary embolism was the cause of cardiac arrest. These patients received only inadequate or no anticoagulation. Early postoperative mobilization, elastic stockings and compressive wound-dressing did not prevent pulmonary embolism. In addition to early postoperative mobilization of the patient and even though there is a risk of perioperative bleeding complications, the use of anticoagulation is highly recommended in surgical procedures like abdominoplasty or dermolipectomy. If sudden dyspnea, chest pain, collapse or cardiac arrest occurs after surgical interventions like these, pulmonary embolism should be considered and further diagnostic steps should be initiated.

Abdomen↗

PubMed2004

Platelet function predicts myocardial damage in patients with acute myocardial infarction.

BACKGROUND: Platelet activation is a hallmark of acute coronary syndromes. Numerous lines of evidence suggest a mechanistic link between von Willebrand factor or platelet hyperfunction and myocardial damage in patients with acute coronary syndromes. Thus, we assessed whether platelet function under high shear rates (collagen adenosine diphosphate closure times [CADP-CTs]) measured with the platelet function analyzer (PFA-100) may be enhanced in patients with myocardial infarction (MI) and whether it may predict the extent of myocardial damage as measured by creatine kinase (CK-MB) or troponin T (TnT) levels. METHODS AND RESULTS: Patients with acute chest pain or symptoms suggestive of acute coronary syndromes (n=216) were prospectively examined at an emergency department. CADP-CT was significantly shorter in patients with MI, particularly in those with an ST-segment-elevation MI (STEMI) compared with the other patient groups (unstable angina, stable coronary artery disease, or controls). Furthermore, CADP-CT and collagen epinephrine-CT at presentation were independent predictors of myocardial damage as measured by CK-MB or TnT. Patients with MI whose CADP-CT values fell in the first quartile had 3-fold higher CK-MB and TnT levels than those in the fourth quartile. CONCLUSIONS: Patients with STEMI have significantly enhanced platelet function when measured under high shear rates. CADP-CT is an independent predictor of the severity of MI, as measured by markers of cardiac necrosis. Measurement of platelet function with the PFA-100 may help in the risk stratification of patients presenting with MI.

Abciximab↗

PubMed2004

Acute chest pain--identification of patients at low risk for coronary events. The impact of symptoms, medical history and risk factors.

BACKGROUND: The evaluation of patients with acute chest pain remains challenging, as it implies the risk of fatal misdiagnosis. It is well recognized that typical angina does not specifically identify patients at high risk. We investigated the predictive value of characteristics atypical for myocardial ischemia for exclusion of acute or subacute coronary events, focusing on patients' symptoms, medical history and risk factors. METHODS: We prospectively studied 1288 consecutive patients presenting with acute chest pain at a non-trauma emergency department. Patients' symptoms, history and risk factors were evaluated using seven predefined criteria and assigned as typical or atypical for ischemic coronary chest pain. Positive predictive value (PPV) and 95% confidence intervals (95% CI) were calculated to predict or exclude acute myocardial infarction (AMI) and major adverse cardiac events (MACE: cardiovascular death, percutaneous coronary interventions, bypass surgery, or myocardial infarction) within six months. RESULTS: AMI occurred in 168 patients (13%), and 6-months MACE (including AMI) overall in 240 patients (19%). Presence of four or more criteria typical for myocardial ischemia was associated with a PPV of 0.21 (0.17 to 0.25) for predicting AMI and 0.30 (0.25 to 0.35) for 6-months MACE. Presence of four or more criteria atypical for coronary ischemia was associated with a PPV of 0.94 (0.91 to 0.96) for excluding AMI and 0.93 (0.90 to 0.96) for excluding 6-months MACE. In 165 of 476 patients under 40 years of age (35%), four or more atypical criteria excluded AMI and 6-months MACE with PPVs of 0.98 (0.96 to 1.0). CONCLUSION: Evaluation of criteria atypical for myocardial ischemia with acute chest pain may help to identify candidates for early discharge, whereas typical characteristics have very little diagnostic value.

Acute Disease↗

PubMed2004

Non-traumatic aortic dissection or rupture as cause of cardiac arrest: presentation and outcome.

OBJECTIVE: To evaluate the frequency, presentation and outcome of non-traumatic aortic dissection/rupture as a cause of cardiac arrest. DESIGN: Retrospective analysis of a cardiac arrest registry in a tertiary care hospital emergency department. RESULTS: Over 11.5 years, aortic dissection/rupture was identified as the immediate cause of cardiac arrest in 46 (2,3%) out of 1990 patients with sudden cardiac arrest, primarily affecting the abdominal aorta in 25 and the thoracic aorta in 21 cases. The characteristics of the 46 patients were as follows: male gender (74%), median age 71 years (IQR 59-76), high co-morbidity (89%), previously known aortic aneurysm (33%), pulseless electric activity (70%) as initial cardiac rhythm. When performed, bedside abdominal sonography or echocardiography was almost always diagnostic. Patients with abdominal aortic dissection/rupture had abdominal (52%) and/or flank pain (32%). Patients with thoracic aortic dissection/rupture complained of chest pain (48%) or dyspnoea (19%). Return of spontaneous circulation occurred in 12 (26%) of 46 patients, emergency surgery was performed in eight of these patients, 2 (4%) survived to discharge in good neurological condition. CONCLUSIONS: Cardiac arrest caused by aortic dissection/rupture is rare, and mortality remains very high, even when circulation can be restored initially. Common features such as previously known aortic aneurysm, old age, male gender and pulseless electrical activity as initial cardiac rhythm should increase suspicion of the condition.

Age Factors↗

PubMed2004

The effect of mild therapeutic hypothermia on renal function after cardiopulmonary resuscitation in men.

BACKGROUND: Mild therapeutic hypothermia (MTH) improves neurological outcome in patients after cardiac arrest. From animal and human studies it appears that hypothermia impairs renal function. The aim of this study was to examine the effects of MTH on renal function in humans. METHODS: Patients were participants recruited in one of the centres of the hypothermia after cardiac arrest-multicenter trial. We measured serum creatinine and creatinine clearance (C(Cr)) within 24 h of MTH, at 4 hourly intervals. Patients were followed for acute renal failure and need for renal supportive therapy for 28 days. RESULTS: We included 60 patients (32 hypothermic, 28 normothermic). Median serum creatinine on admission was [[119 micromol/l (IQR 108-133)] [1.35 mg/dl (IQR 1.22-1.50)]] in hypothermic and [[114 micromol/l (IQR 99-131)] [1.29 mg/dl (IQR 1.12-1.48)]] in normothermic patients, and decreased to [[69 micromol/l (IQR 62-84)] [0.78 mg/dl (IQR 0.70-0.95)]] in the hypothermic group and to [[88 micromol/l (IQR 71-123)] [1.00 mg/dl (IQR 0.80-1.39)]] in the normothermic group within 24h. C(Cr) was decreased on admission. Within 24 h C(Cr) improved to normal values in normothermic patients [1.53 ml/s (IQR 1.15-2.35) [92 ml/min (IQR 69-141)]] and remained low in hypothermic patients [0.88 ml/s (IQR 0.63-1.38) [53 ml/min (IQR 38-83)]] (P = 0.0006). No difference was found between the groups in the development of acute renal failure or the need for renal supportive therapy. CONCLUSION: Twenty four hours of MTH was associated with a delayed improvement in renal function. This was not reflected in the serum creatinine values, which were low in the hypothermic group. This transient impaired renal function appeared to be completely reversible within 4 weeks.

Acute Kidney Injury↗

PubMed2004

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.

Cardiopulmonary Resuscitation↗

PubMed2004

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.

Cardiopulmonary Resuscitation↗

PubMed2004

Serial lactate determinations for prediction of outcome after cardiac arrest.

We investigated the relationship between lactate clearance and outcome in patients surviving the first 48 hours after cardiac arrest. We conducted the study in the emergency department of an urban tertiary care hospital. We analyzed the data for all 48-hour survivors after successful resuscitation from cardiac arrest during a 10-year period. Serial lactate measurements, demographic data, and key cardiac arrest data were correlated to survival and best neurologic outcome within 6 months after cardiac arrest. Parameters showing significant results in univariate analysis were tested for significance in a logistic regression model. Of 1502 screened patients, 394 were analyzed. Survivors (n = 194, 49%) had lower lactate levels on admission (median, 7.8 [interquartile range, 5.4-10.8] vs 9 [6.6-11.9] mmol/L), after 24 hours (1.4 [1-2.5] vs 1.7 [1.1-3] mmol/L), and after 48 hours (1.2 [0.9-1.6] vs 1.5 [1.1-2.3] mmol/L). Patients with favorable neurologic outcome (n = 186, 47%) showed lower levels on admission (7.6 [5.4-10.3] vs 9.2 [6.7-12.1] mmol/L) and after 48 hours (1.2 [0.9-1.6] vs 1.5 [1-2.2] mmol/L). In multivariate analysis, lactate levels at 48 hours were an independent predictor for mortality (odds ratio [OR]: 1.49 increase per mmol/L, 95% confidence interval [CI]: 1.17-1.89) and unfavorable neurologic outcome (OR: 1.28 increase per mmol/L, 95% CI: 1.08-1.51). Lactate levels higher than 2 mmol/L after 48 hours predicted mortality with a specificity of 86% and poor neurologic outcome with a specificity of 87%. Sensitivity for both end points was 31%. Lactate at 48 hours after cardiac arrest is an independent predictor of mortality and unfavorable neurologic outcome. Persisting hyperlactatemia over 48 hours predicts a poor prognosis.

Age Factors↗