Related Cardiac Arrest Research Articles

Characteristics and outcome among patients suffering from in hospital cardiac arrest in relation to the interval between collapse and start of CPR

Aim: To describe survival after in-hospital cardiac arrest in relation to the interval between collapse and start of cardiopulmonary resuscitation (CPR). Patients: All patients suffering in-hospital cardiac arrest in Sahlgrenska University Hospital in Göteborg, Sweden between 1994 and 1999 in whom resuscitative efforts were attempted and for whom the interval between collapse and start of CPR was known. Methods: Prospective recording of various factors at resuscitation including the interval between collapse and start of CPR. Retrospective evaluation via medical records of patients’ previous history, clinical situation prior to cardiac arrest and final outcome. Results: Survival to discharge was 33% among the 344 patients in whom CPR was started within the first minute as compared with 14% among the 88 patients in whom CPR started more than 1 min after collapse ( P=0.008). The corresponding figures for patients found in ventricular fibrillation was 50 versus 32% (NS); for patients found in pulseless electrical activity 9 versus 3% (NS) and for patients found in asystole 19 versus 0% (NS). Correcting for dissimililarties in the previous history and factors at resuscitation, the adjusted odds ratio and 95% confidence limits for being discharged from hospital when CPR was started within 1 min compared with a later start was 3.06 with 95% confidence limits of 1.59–6.31. Conclusion: Among patients with in-hospital cardiac arrest in whom the interval between collapse and start of CPR was known, we found that in 80% of the cases CPR was started within the first minute after collapse. Among these patients, survival to discharge was twice that of patients in whom CPR was started later. These results highlight the importance of immediate CPR after in-hospital cardiac arrest.

Characteristics and outcome among patients suffering in-hospital cardiac arrest in monitored and non-monitored areas

Aim: To describe the characteristics and outcome among patients suffering in-hospital cardiac arrest in relation to whether the arrest took place in a ward with monitoring facilities. Methods: All patients who suffered an in-hospital cardiac arrest during a 4-year period in Sahlgrenska Hospital, Göteborg, Sweden and in whom resuscitative efforts were attempted, were prospectively recorded and described in terms of characteristics and outcome. Results: Among 557 patients, 292 (53%) had a cardiac arrest in wards with monitoring facilities. Those in a monitored location more frequently had a confirmed or possible acute myocardial infarction (AMI) as judged to be the cause of arrest ( P<0.0001), and the arrest was witnessed more frequently (96 vs. 79%; P<0.0001). Ventricular fibrillation/tachycardia was observed more often as initial arrhythmia in monitored wards (56 vs. 44%; P=0.006). The median interval between collapse and first defibrillation was 1 min in monitored wards and 5 min in non-monitored wards ( P<0.0001). Among patients with arrest in monitored wards 43.2% were discharged alive compared with 31.1% of patients in non-monitored wards ( P=0.004). Cerebral performance category (CPC-score) at discharge was somewhat better among survivors in monitored wards. Conclusion: In a Swedish University Hospital 47% of in-hospital cardiac arrests in which resuscitation was attempted took place in wards without monitoring facilities. These patients differed markedly from those having arrest in wards with monitoring facilities in terms of characteristics, interval to defibrillation and outcome. A shortening of the interval between collapse and defibrillation in these patients might increase survival even further.

Outcomes of patients hospitalized after out-of-hospital cardiac arrest in relation to sex.

To describe characteristics and outcomes of patients hospitalized after out-of-hospital cardiac arrest in relation to sex. All patients in the community of Göteborg who between 1980 and 1996 suffered out-of-hospital cardiac arrest and were hospitalized alive. We calculated age-adjusted P values. In all 1038 patients were hospitalized alive of whom 29% were women. Women differed from men by being older and there being lower prevalences of previous acute myocardial infarction (AMI) and smoking and a higher prevalence of bronchial asthma among them. They had less commonly received cardio-pulmonary resuscitation (CPR) from bystanders (16 versus 25% of cases; P = 0.002) and were less commonly found to be in ventricular fibrillation when the ambulance crew arrived (55 versus 73% of cases; P < 0.0001). They were less commonly judged to have a cardiac etiology behind the arrest (87 versus 92% of cases; P = 0.016). Of women 31.3% could be discharged alive from hospital, compared with 41.8% of men (P = 0.001). While they were in hospital, women were less commonly subjected to exercise tests, coronary angiography, and coronary artery bypass grafting. Among patients who suffered out-of-hospital cardiac arrest and were hospitalized alive, women had less commonly received CPR from bystanders, were less commonly found in ventricular fibrillation, less commonly underwent coronary angiography and coronary artery bypass grafting and had a lower survival rate than did men.

Pharmacologically induced embryonic dysrhythmia and episodes of hypoxia followed by reoxygenation: a common teratogenic mechanism for antiepileptic drugs?

Antiepileptic drugs (AEDs), such as phenytoin (PHT), carbamazepine (CBZ), trimethadione (TMD), and phenobarbital (PB), have all been associated with a similar pattern of malformations, as well as growth retardation and developmental delay. Valproic acid (VPA) has been associated with a different pattern of malformations. Recent studies suggest that PHT's fetal adverse effect is related to its membrane stabilizing pharmacological properties (blockage of voltage-dependent ion channels). During a restricted sensitive period, this results in induction of concentration-dependent bradyarrhythmia in the embryo and episodes of hypoxia/reoxygenation. The aim of this study was to compare the potential of PHT, CBZ, PB, TMD, and dimethadione (DMD; the active metabolite of TMD) to cause bradyarrhythmias. All of these AEDs exert mainly their pharmacological effect via blockage of ion channels. VPA and vigabatrin (VGB), which are pharmacologically active mainly by other mechanisms, were also tested. C57 Bl/6J mouse embryos were cultured in vitro on gestation day 10 in vitro (in 20% rat serum). The drugs were suspended in either water or dimethylsulfoxide and administered into the culture medium in increasing concentrations up to 20 times the human therapeutic plasma concentration. A scoring system was employed in order to rank the drugs based on their potential to cause bradycardia, ventricular arrhythmia, and cardiac arrest in relation to human therapeutic concentrations. Based on this system, the drugs were ranked as follows: DMD = PHT >> PB = CBZ > TMD = VPA >> VGB (no potential). The results correlate well with the available clinical/experimental data of the tested AED's potential to induce hypoxia-related fetal adverse effects, such as oral clefts, distal limb defects, growth retardation, and developmental delay. The results support the idea that adverse fetal effects after in utero exposure to PHT, PB, CBZ, and TMD (via the active metabolite DMD) are initiated via a common pharmacological mechanism: blockage of ion channels in the developing heart in the early embryo resulting in bradyarrhythmias, hemodynamic alterations, and hypoxia/reoxygenation damage.

Type of arrhythmia at EMS arrival on scene in out-of-hospital cardiac arrest in relation to interval from collapse and whether a bystander initiated CPR: Am J Emerg Med 1996; 14/2: 119–123

Outcome after cardiac arrest is strongly related to whether the patient has ventricular fibrillation at the time the emergency medical service (EMS) arrives on the scene. The occurrence of various arrhythmias at the time of EMS arrival among patients with out-of-hospital cardiac arrest was studied in relation to the interval from collapse and whether cardiopulmonary resuscitation (CPR) was initiated by a bystander. The patients studied were all those with out-of-hospital cardiac arrest in Goteborg, Sweden, between 1980 and 1992 in whom CPR was attempted by the arriving EMS and for whom the interval between collapse and the arrival of EMS was known. In all, information on the time of collapse and arrival of EMS was available for 1,737 patients. Among patients for whom EMS arrived within 4 minutes of collapse, 53% were found in ventricular fibrillation/tachycardia. There was a successive decline in the occurrence of such arrhythmias with time. However, when the interval exceeded 20 minutes, ventricular fibrillation/tachycardia was still observed in 27% of cases. Bystander CPR increased the occurrence of such arrhythmias regardless of the interval between collapse and EMS arrival.

Type of arrhythmia at EMS arrival on scene in out-of-hospital cardiac arrest in relation to interval from collapse and whether a bystander initiated CPR

Outcome after cardiac arrest is strongly related to whether the patient has ventricular fibrillation at the time the emergency medical service (EMS) arrives on the scene. The occurrence of various arrhythmias at the time of EMS arrival among patients with out-of-hospital cardiac arrest was studied in relation to the interval from collapse and whether cardiopulmonary resuscitation (CPR) was initiated by a bystander. The patients studied were all those with out-of-hospital cardiac arrest in Göteborg, Sweden, between 1980 and 1992 in whom CPR was attempted by the arriving EMS and for whom the interval between collapse and the arrival of EMS was known. In all, information on the time of collapse and arrival of EMS was available for 1,737 patients. Among patients for whom EMS arrived within 4 minutes of collapse, 53% were found in ventricular fibrillation/tachycardia. There was a successive decline in the occurrence of such arrhythmias with time. However, when the interval exceeded 20 minutes, ventricular fibrillation/tachycardia was still observed in 27% of cases. Bystander CPR increased the occurrence of such arrhythmias regardless of the interval between collapse and EMS arrival.