Objective : To investigate the efficacy and safty of radiofrequency ablation for arrhythmia. Methods: The clinical data of 1 065 patients with arrhythmia by Radiofrequency ablation treatment were analyzed retrospectively, including 537 cases of atrioventricular nodal reentrant tachycardia, 386 cases of atrioventricular reentrant tachycardia, 59 cases of ventricular premature, 26 cases of ventricular tachycardia, 35 cases of atrial flutter, and 8 cases of paroxysmal atrial fibrillation. Results:The procedural succeed rate was 96. 80% , and complication was 1. 56%. Conclusion: Radiofrequency ablation was an safe and effective method in treating arrhythmia.

OBJECTIVETo study the effects of high frequency oscillatory ventilation (HFOV) with different position on oxygenation and hemodynamics of dogs with severe smoke inhalation injury.

METHODSAfter being treated with conventional mechanical ventilation, 12 dogs were inflicted with severe smoke inhalation injury and treated by HFOV for 30 min. They were divided into HFOV+prone positioning (PP) group and HFOV+supine positioning (SP) group according to the random number table, with 6 dogs in each group. They received HFOV with corresponding position for 8 hours respectively.

RESULTSof blood gas analysis (pH, PaO₂ and PaCO₂ levels), oxygen index (OI) and hemodynamic parameters [heart rate, mean arterial pressure (MAP), and cardiac output (CO)] were recorded or calculated before injury, immediately after injury, and at post ventilation hour (PVH) 2, 4, 6, 8. Data were processed with analysis of variance of repeated measurement, and LSD- t test.

RESULTS(1) At PVH 8, pH value of dogs in group HFOV+PP was significantly higher than that in group HFOV+SP (t = 3.0571, P < 0.05). Compared with those observed immediately after injury, except for group HFOV+SP at PVH 2 and 4 (with t values respectively 2.066 5 and 1.440 7, P values all above 0.05), the pH values in both groups at other treatment time points were decreased (with t values from 2.449 5 to 3.985 3, P < 0.05 or P < 0.01). At PVH 2, 4, 8, the PaO₂ levels in group HFOV+PP [(131 ± 26), (150 ± 40), (112 ± 30) mmHg, 1 mmHg = 0.133 kPa] were higher than those in group HFOV+SP [(81 ± 15), (96 ± 5), (83 ± 6) mmHg, with t values from 2.366 4 to 4.083 5, P < 0.05 or P < 0.01]. The PaO₂ levels in both groups from PVH 2 to PVH 8 were increased, compared with those observed immediately after injury [(55 ± 15) mmHg in group HFOV+SP and (48 ± 11) mmHg in group HFOV+PP, with t values from 2.473 6 to 7.2310, P < 0.05 or P < 0.01]. No statistically significant differences were observed in PaCO₂ level at each time point between two groups (with t values from 0.661 0 to 2.141 9, P values all above 0.05). No statistically significant differences were observed in PaCO₂ levels from PVH 2 to PVH 8 compared with those observed immediately after injury in both groups (with t values from 0.126 2 to 1.768 3, P values all above 0.05). (2) The OI values in group HFOV+SP were significantly higher than those in group HFOV+PP from PVH 2 to PVH 8 (with t values from 3.091 9 to 3.791 6, P < 0.05 or P < 0.01). The OI values in both groups from PVH 2 to PVH 8 were significantly decreased, compared with those observed immediately after injury (with t values from 2.702 0 to 5.969 3, P < 0.05 or P < 0.01). (3) At PVH 6 and PVH 8, heart rate in group HFOV+PP was significantly higher than that in group HFOV+SP (with t values respectively 4.255 9 and 4.765 9, P values both below 0.01). Compared with that observed immediately after injury, heart rate in group HFOV+PP was significantly decreased (with t values from 3.006 2 to 5.135 5, P < 0.05 or P < 0.01) except for PVH 2 (t = 1.938 2, P > 0.05). However, there was no statistical significant difference at each treatment time point in group HFOV+PP (with t values from 0.786 5 to 1.525 8, P values all above 0.05). There was no statistically significant difference in MAP between two groups at each time point (with t values from 0.045 8 to 1.783 4, P values all above 0.05). Compared with that observed immediately after injury, MAP in group HFOV+SP was significantly decreased at PVH 8 (t = 2.368 3, P < 0.05); MAP in group HFOV+PP was significantly decreased at PVH 2 (t = 3.580 1, P < 0.01). At PVH 2 and 4, the CO values in group HFOV+SP were significantly higher than those in group HFOV+PP (with t values respectively 2.310 3 and 4.526 5, P values both below 0.01). Except for group HFOV+SP at PVH 2 (t = 1.294 1, P > 0.05), CO values at other treatment time points in both groups were significantly lower than that observed immediately after injury (with t values from 2.247 0 to 4.067 8, P < 0.05 or P < 0.01).

CONCLUSIONSHFOV+ PP can improve oxygenation with no obvious CO₂ retention or adverse effect on hemodynamic parameters of dogs with severe smoke inhalation injury. Therefore, it is recommended for clinical application.

Animals ; Carbon Dioxide ; blood ; Disease Models, Animal ; Dogs ; Hemodynamics ; High-Frequency Ventilation ; Male ; Oxygen ; blood ; Prone Position ; Smoke Inhalation Injury ; physiopathology ; therapy ; Supine Position