Cardiopulmonary resuscitation by chest compression alone or with mouth-to-mouth ventilation.
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BACKGROUND: Despite extensive training of citizens of Seattle in cardiopulmonary resuscitation (CPR), bystanders do not perform CPR in almost half of witnessed cardiac arrests. Instructions in chest compression plus mouth-to-mouth ventilation given by dispatchers over the telephone can require 2.4 minutes. In experimental studies, chest compression alone is associated with survival rates similar to those with chest compression plus mouth-to-mouth ventilation. We conducted a randomized study to compare CPR by chest compression alone with CPR by chest compression plus mouth-to-mouth ventilation. METHODS: The setting of the trial was an urban, fire-department-based, emergency-medical-care system with central dispatching. In a randomized manner, telephone dispatchers gave bystanders at the scene of apparent cardiac arrest instructions in either chest compression alone or chest compression plus mouth-to-mouth ventilation. The primary end point was survival to hospital discharge. RESULTS: Data were analyzed for 241 patients randomly assigned to receive chest compression alone and 279 assigned to chest compression plus mouth-to-mouth ventilation. Complete instructions were delivered in 62 percent of episodes for the group receiving chest compression plus mouth-to-mouth ventilation and 81 percent of episodes for the group receiving chest compression alone (P=0.005). Instructions for compression required 1.4 minutes less to complete than instructions for compression plus mouth-to-mouth ventilation. Survival to hospital discharge was better among patients assigned to chest compression alone than among those assigned to chest compression plus mouth-to-mouth ventilation (14.6 percent vs. 10.4 percent), but the difference was not statistically significant (P=0.18). CONCLUSIONS: The outcome after CPR with chest compression alone is similar to that after chest compression with mouth-to-mouth ventilation, and chest compression alone may be the preferred approach for bystanders inexperienced in CPR. (+info)
Efficacy of continuous insufflation of oxygen combined with active cardiac compression-decompression during out-of-hospital cardiorespiratory arrest.
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BACKGROUND: During experimental cardiac arrest, continuous insufflation of air or oxygen (CIO) through microcannulas inserted into the inner wall of a modified intubation tube and generating a permanent positive intrathoracic pressure, combined with external cardiac massage, has previously been shown to be as effective as intermittent positive pressure ventilation (IPPV). METHODS: After basic cardiorespiratory resuscitation, the adult patients who experienced nontraumatic, out-of-hospital cardiac arrest with asystole, were randomized to two groups: an IPPV group tracheally intubated with a standard tube and ventilated with standard IPPV and a CIO group for whom a modified tube was inserted, and in which CIO at a flow rate of 15 l/min replaced IPPV (the tube was left open to atmosphere). Both groups underwent active cardiac compression-decompression with a device. Resuscitation was continued for a maximum of 30 min. Blood gas analysis was performed as soon as stable spontaneous cardiac activity was restored, and a second blood gas analysis was performed at admission to the hospital. RESULTS: The two groups of patients (47 in the IPPV and 48 in the CIO group) were comparable. The percentages of patients who underwent successful resuscitation (stable cardiac activity; 21.3 in the IPPV group and 27.1% in the CIO group) and the time necessary for successful resuscitation (11.8 +/- 1.8 and 12.8 +/- 1.9 min) were also comparable. The blood gas analysis performed after resuscitation (8 patients in the IPPV and 10 in the CIO group) did not show significant differences. The arterial blood gases performed after admission to the hospital and ventilation using a transport ventilator (seven patients in the IPPV group and six in the CIO group) showed that the partial pressure of arterial carbon dioxide (PaCO2) was significantly lower in the CIO group (35.7 +/- 2.1 compared with 72.7 +/- 7.4 mmHg), whereas the pH and the partial pressure of arterial oxygen (PaO2) were significantly higher (all P < 0.05). CONCLUSIONS: Continuous insufflation of air or oxygen alone through a multichannel open tube was as effective as IPPV during out-of-hospital cardiac arrest. A significantly greater elimination of carbon dioxide and a better level of oxygenation in the group previously treated with CIO probably reflected better lung mechanics. (+info)
Right atrial laceration. Complication of external cardiac massage.
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Right atrial laceration is described as a complication of external cardiac massage in two patients. In each there was a pre-existent cause of weakness of the atrial wall. There was pronounced right atrial dilation with attenuation of the wall in one case, and in the other there was a granulomatous myocarditis involving the atrial wall. The significance of atrial laceration as a complication of traumatic injuries to the heart is discussed. (+info)
Adverse hemodynamic effects of interrupting chest compressions for rescue breathing during cardiopulmonary resuscitation for ventricular fibrillation cardiac arrest.
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BACKGROUND: Despite improving arterial oxygen saturation and pH, bystander cardiopulmonary resuscitation (CPR) with chest compressions plus rescue breathing (CC+RB) has not improved survival from ventricular fibrillation (VF) compared with chest compressions alone (CC) in numerous animal models and 2 clinical investigations. METHODS AND RESULTS: After 3 minutes of untreated VF, 14 swine (32+/-1 kg) were randomly assigned to receive CC+RB or CC for 12 minutes, followed by advanced cardiac life support. All 14 animals survived 24 hours, 13 with good neurological outcome. For the CC+RB group, the aortic relaxation pressures routinely decreased during the 2 rescue breaths. Therefore, the mean coronary perfusion pressure of the first 2 compressions in each compression cycle was lower than those of the final 2 compressions (14+/-1 versus 21+/-2 mm Hg, P<0.001). During each minute of CPR, the number of chest compressions was also lower in the CC+RB group (62+/-1 versus 92+/-1 compressions, P<0.001). Consequently, the integrated coronary perfusion pressure was lower with CC+RB during each minute of CPR (P<0.05 for the first 8 minutes). Moreover, at 2 to 5 minutes of CPR, the median left ventricular blood flow by fluorescent microsphere technique was 60 mL. 100 g(-1). min(-1) with CC+RB versus 96 mL. 100 g(-1). min(-1) with CC, P<0.05. Because the arterial oxygen saturation was higher with CC+RB, the left ventricular myocardial oxygen delivery did not differ. CONCLUSIONS: Interrupting chest compressions for rescue breathing can adversely affect hemodynamics during CPR for VF. (+info)
Importance of continuous chest compressions during cardiopulmonary resuscitation: improved outcome during a simulated single lay-rescuer scenario.
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BACKGROUND: Interruptions to chest compression-generated blood flow during cardiopulmonary resuscitation (CPR) are detrimental. Data show that such interruptions for mouth-to-mouth ventilation require a period of "rebuilding" of coronary perfusion pressure to obtain the level achieved before the interruption. Whether such hemodynamic compromise from pausing to ventilate is enough to affect outcome is unknown. METHODS AND RESULTS: Thirty swine (weight 35 +/- 2 kg) underwent 3 minutes of untreated ventricular fibrillation before 12 minutes of basic life support CPR. Animals were randomized to receive either standard airway (A), breathing (B), and compression (C) CPR with expired-gas ventilation in a 15:2 compression-to-ventilation ratio or continuous chest compression CPR. Those randomized to the standard 15:2 group had no chest compressions for a period of 16 seconds each time the 2 ventilations were delivered. Defibrillation was attempted at 15 minutes of cardiac arrest. All resuscitated animals were supported in an intensive care environment for 1 hour, then in a maintenance facility for 24 hours. The primary end point of neurologically normal 24-hour survival was significantly better in the experimental group receiving continuous chest compression CPR (12 of 15 versus 2 of 15; P<0.0001). CONCLUSIONS: Mouth-to-mouth ventilation performed by single layperson rescuers produces substantial interruptions in chest compression-supported circulation. Continuous chest compression CPR produces greater neurologically normal 24-hour survival than standard ABC CPR when performed in a clinically realistic fashion. Any technique that minimizes lengthy interruptions of chest compressions during the first 10 to 15 minutes of basic life support should be given serious consideration in future efforts to improve outcome results from cardiac arrest. (+info)
Perinatal cardiac arrest. Quality of the survivors.
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Steiner, H., and Neligan, G. (1975). Archives of Disease in Childhood, 50, 696. Perinatal cardiac arrest: quality of the survivors. Twenty-two consecutive survivors of perinatal cardiac arrest have been followed to a mean age of 4 1/4 years, using methods of neurological and developmental assessment appropriate to their ages. 4 showed evidence of gross, diffuse brain-damage (2 of these died before the age of 3 years). These were the only 4 survivors of the first month of life who took more than 30 minutes to establish regular, active respiration after their heartbeat had been restored. The arrest in these cases had occurred during or within 15 minutes of delivery, and followed antepartum haemorrhage, breech delivery, or prolapsed cord. The remaining 18 were free of any evidence of brain damage. In the majority of these the arrest had occurred during shoulder dystocia or exchange transfusion, or was unexplained; the heartbeat had been restored within 5 minutes in most cases, and regular, active respiration had been established within 30 minutes thereafter in all cases. (+info)
Presence of a carotid bruit in adults with unexplained or recurrent falls: implications for carotid sinus massage.
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BACKGROUND: Carotid sinus hypersensitivity is a common cardiovascular cause of unexplained or recurrent falls in older adults. Effective treatment is available once carotid sinus hypersensitivity is identified. Carotid sinus massage is the only practical method for achieving a diagnosis. Carotid sinus massage is contraindicated if a carotid bruit is present. OBJECTIVE: To determine the prevalence of carotid sinus hypersensitivity in adults presenting with unexplained or recurrent falls and a carotid bruit. DESIGN: Prospective consecutive cohort study. SETTING: Accident and Emergency department and regional syncope and falls facility. SUBJECTS: Accident and Emergency patients aged 50 years or over with unexplained or recurrent falls and a carotid bruit. INTERVENTION: 1) Carotid doppler ultrasound to identify significant stenosis (> or = 50%). 2) Carotid sinus massage (with electrocardiographic and phasic blood pressure monitoring) was performed supine and possibly upright. METHODS: Consecutive adults with unexplained or recurrent falls were screened for carotid bruits. Those with a carotid bruit were referred for carotid Doppler ultrasound and stratified for further investigation depending on presence and degree of underlying carotid artery stenosis. Carotid sinus massage was performed at least supine in those with up to moderate stenosis (50-69%) in either internal or common carotid artery. MAIN OUTCOME MEASURE: Diagnosis of carotid sinus hypersensitivity. RESULTS: We identified 1682 subjects with unexplained or recurrent falls of whom 179 (11%) had a carotid bruit, 167 underwent ultrasound, 31% had a stenosis > or = 50% (20% > or = 70%) in either internal or common carotid artery. A bruit was associated with significant ipsilateral stenosis in 25% and contralateral silent stenosis in a further 5%. Carotid sinus massage was performed in 121 subjects who were suitable (15 with moderate carotid artery stenosis). Carotid sinus hypersensitivity was found in 41 (34%) subjects (4 with moderate stenosis). No serious complications occurred following carotid sinus massage. CONCLUSIONS: Carotid sinus hypersensitivity is a possible attributable cause of symptoms in a third of subjects with unexplained or recurrent falls and carotid bruits. Only a small number have severe carotid artery stenosis. Ultrasound will identify high-risk subjects and facilitate accurate diagnosis with carotid sinus massage in the majority. (+info)
Unexpected resistance to external cardiac compression may signal pericardial tamponade.
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Pericardial tamponade associated with central catheters is often lethal, unless promptly identified. We report our experience with two infants who suffered this complication but were successfully resuscitated. In each case, associated radiographs showed the tip of the central catheter beyond the superior vena cava-right atrium (SVC-RA) junction. Identifying the clinical triad of (1) sudden cardiovascular collapse unresponsive to usual resuscitative measures, (2) thoracic transillumination not suggestive of air leak, and (3) unexpected resistance to external cardiac compression led to the working diagnosis of pericardial tamponade and therapeutic pericardiocentesis. Prompt recovery followed. Central catheters within the RA seem prone to cause pericardial tamponade. (+info)