黄莹山
OBJECTIVE:This study aims to investigate the methods for rat spinal cord ischemia injury models with a high long-term survival rate.METHODS:The rats were divided into three groups: the treatment group, the control group, and the sham operation group. The treatment group had a blocked thoracic aorta (landing zone 3 by Ishimaru - T11) + aortic bypass circulation for 20 min. In the control group, the thoracic aorta at the landing zone 3 was blocked for 20 min. In the sham operation group, only thoracotomy without thoracic aortic occlusion was performed. The mean arterial blood pressure (MABP) of the thoracic aorta and caudal artery before and after thoracic aortic occlusion was monitored intraoperatively. Spinal cord function was monitored by a transcranial motor evoked potential (Tc-MEP) during the operation. Spinal cord function was evaluated by the BBB scale (Basso, Beattie, & Bresnahan locomotor rating scale) scores at multiple postoperative time points. The spinal cord sections of the rats were observed for 7 days after surgery, and the survival curves were analyzed for 28 days after surgery.RESULTS:After aortic occlusion, the MABP of thoracic aorta decreased to 6% of that before occlusion, and the MABP of caudal artery decreased to 63% of that before occlusion in the treatment group. In the control group, the MABP of both thoracic aorta and caudal artery decreased to 19% of that before occlusion. The Tc-MEP waveform of the treatment group disappeared after 6 min, and that of the control group disappeared after 8 min until the end of surgery. There was no change in the Tc-MEP waveform in the sham operation group. The BBB score of the treatment group decreased more obviously than the control group, and there was a significant difference. There was no decrease in the sham group. Spinal cord sections showed a large number of degeneration and necrosis of neurons, infiltration of inflammatory cells, and proliferation of surrounding glial cells in the treatment group. In the control group, multiple neurons were necrotic. The histology of the sham operation group was normal. The 28-day survival rate of the treatment group was 73.3%, which was higher than the control group (40.0%), and there was a significant difference (p < 0.05).CONCLUSION:Thoracic aortic occlusion combined with aortic bypass is an effective modeling method for rats with accurate modeling effects and high long-term survival rates.
Vascular 2023
BACKGROUND:Myocardial protection is essential in cardiac surgery with cardiopulmonary bypass The Del Nido cardioplegia which was initially used in pediatric cardiac surgery, has been increasingly used in adult cardiac surgery recently. However, no literature has reported the efficacy of DNC in hypertrophic obstructive cardiomyopathy.METHODS:This retrospective study involved elective patients who underwent extended surgical myectomy with or without concomitant cardiac surgical procedures between September 2017 and June 2022. Patients were distributed into two groups, the DNC and the CBC group. The primary outcome was high-sensitivity cardiac troponin I (hs-TnI) and creatine kinase-MB (CK-MB) levels at the 0, 1, and 2 postoperative days. The secondary outcomes contained: intraoperative LVEF, return to spontaneous rhythm; postoperative myocardial infarction, worsening or deteriorating of EF, mechanical circulatory support; new-onset atrial fibrillation; mechanical ventilation duration; intensive care unit hours; in-hospital days.RESULTS:Fifty-nine patients were included and divided into the CBC (n = 15) and the DNC group (n = 44). There was no statistical difference in patients' demographics and preoperative parameters between the two groups. No in-hospital mortality. The total cardioplegia volume [21.93(18.36,26.07) vs. 25.68(23.17,37.12), p = 0.012] and infusion times [1(1,1) vs. 2(2,3), p = 0.000] were less and the incidence of return to spontaneous rhythm after declamping was higher in the DNC group [97.7% vs. 73.3%, p = 0.013]. Postoperative hs-TnI and CK-MB levels were comparable between the two groups. A longer DNC infusion interval was associated with higher levels of CK-MB on postoperative day 1 and day 2 (p = 0.009 and p = 0.011, respectively).CONCLUSIONS:The use of DNC in extended surgical myectomy procedure was as safe and effective as CBC. However, DNC infusion interval over 60 minutes was associated with increased postoperative CK-MB levels.
Perfusion 2023