| Author/Editor | Pernat, Andrej | |
| Title | Analiza aktivnosti preddvorov in nadzor učinkovitosti zunanje masaže srca med oživljanjem | |
| Type | monografija | |
| Place | Ljubljana | |
| Publisher | Medicinska fakulteta | |
| Publication year | 2000 | |
| Volume | str. 70 | |
| Language | slo | |
| Abstract | First set of experiments was designed to investigate atrial mechanical and electrical functions during ventricular fibrillation (VF) of 8 min or longer duration. In addition, we wanted to quantitate the amount and direction of blood flow generated by atrial contractions in this setting. To demonstrate preserved electrical function of the atria, epicardial right atrial electrograms in the isolated rat hearts were recorded during VF. To demonstrate preserved atrial contractions we continuously recorded right atrial pressure pulses prior to and during VF in 10 rats. Finally, we measured magnitude and direction of blood flow across the mitral valve during VF in 15 pigs utilizing transesophageal echo-Doppler methodologies. In isolated perfused rat hearts, we demonstrated regular atrial depolarizations that accompanied atrial contractions during VF. In each of the rats regular right atrial pressure pulsations were demonstrated during VF. These persisted over an average interval of 7.5 min. In pigs, atrial contractions generated stroke volumes of approximately 12 ml or 25 % of pre-arrest values during the first minute after the onset of VF. Stroke volumes gradually declined to approximately 6 ml after 10 min of untreated arrest. However, blood flow from the left atrium failed to advance significantly into systemic circuit. During atrial diastole we observed reversal of blood flow into the left atrium. In conclusion, atrial contractions are preserved during the initial 8 min or more after the onset of VF. Substantial forward flow generated by atrial contractions failed to advance into the systemic circuit. In the second set of experiments our goal was to measure stroke volumes produced by precordial compression during cardiopulmonary resuscitation and to quantitate relationships of stroke volume to measurements of end-tidal carbon dioxide (ETCO2). Eighteen anestethized pigs weighing between 40 and 45 kg were investigated. (Abstract truncated at 2000 characters) | |
| Descriptors | VENTRICULAR FIBRILLATION HEART ATRIUM ELECTROCARDIOGRAPHY MYOCARDIAL CONTRACTION ECHOCARDIOGRAPHY, TRANSESOPHAGEAL RATS SWINE ATRIAL FUNCTION HEART ARREST STROKE VOLUME CARDIOPULMONARY RESUSCITATION RESPIRATION, ARTIFICIAL CARDIAC OUTPUT |