Wang Pei, Zhang Lei, Gong Yushun, Zhang Hehua, Wang Xiang, Li Yongqin
*School of Biomedical Engineering †Emergency Department, Southwest Hospital ‡Department of Medical Engineering, Daping Hospital and Research Institute of Surgery §Department of Ultrasound, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing, China.
Shock. 2016 Apr;45(4):434-40. doi: 10.1097/SHK.0000000000000510.
Systemic hypertension and left ventricular hypertrophy (LVH) are major risk factors of cardiac arrest. However, the impacts of hypertension and LVH on the outcome of cardiopulmonary resuscitation (CPR) and post-resuscitation hypothermia are still undetermined.
After 4 min of untreated ventricular fibrillation (VF) and 4 min of CPR, defibrillation was attempted in 16 male spontaneously hypertensive rats (SHR) with LVH and 16 male normotensive Wistar Kyoto (WKY) rats. When restoration of spontaneous circulation (ROSC) was achieved, animals were randomized into either hypothermia or normothermia. For animals subjected to hypothermia, rapid cooling was started immediately after ROSC and a temperature of 33.0 ± 0.4°C was maintained for 2 h. Normothermic animals were maintained at 37.0 ± 0.4°C.
Baseline mean arterial pressure, heart rate, and left ventricle mass were significantly higher but ejection fraction was lower for hypertensive animals. Coronary perfusion pressure was higher for SHR, but no differences in duration of CPR and number of defibrillations required for resuscitation compared with WKY. All of the animals were successfully resuscitated but post-resuscitation cardiac function was severely impaired in hypertensive animals. Serum levels of cardiac troponin T, amino-terminal pro-brain natriuretic peptide, and S100B measured after ROSC were also markedly higher in SHR groups. Fourteen WKY rats (87.5%) survived, whereas only 1 SHR (6.3%, P < 0.001) survived to 96 h.
In this rat model, systemic hypertension and LVH did not affect ROSC. However, survival was dismal due to elevated severity of cardiac and cerebral injury in hypertensive animals regardless of short-duration hypothermia.
系统性高血压和左心室肥厚（LVH）是心脏骤停的主要危险因素。然而，高血压和LVH对心肺复苏（CPR）结果及复苏后低温的影响仍未明确。
在16只患有LVH的雄性自发性高血压大鼠（SHR）和16只雄性正常血压的Wistar Kyoto（WKY）大鼠中，在未经治疗的室颤（VF）4分钟和CPR 4分钟后尝试进行除颤。当实现自主循环恢复（ROSC）后，将动物随机分为低温组或常温组。对于接受低温治疗的动物，在ROSC后立即开始快速降温，并将温度维持在33.0±0.4°C达2小时。常温动物维持在37.0±0.4°C。
高血压动物的基线平均动脉压、心率和左心室质量显著更高，但射血分数更低。SHR的冠状动脉灌注压更高，但与WKY相比，CPR持续时间和复苏所需除颤次数无差异。所有动物均成功复苏，但高血压动物复苏后的心脏功能严重受损。ROSC后测量的心脏肌钙蛋白T、氨基末端脑钠肽前体和S100B的血清水平在SHR组中也明显更高。14只WKY大鼠（87.5%）存活，而只有1只SHR（6.3%，P<0.001）存活至96小时。
在该大鼠模型中，系统性高血压和LVH不影响ROSC。然而，无论短时间低温治疗如何，高血压动物因心脏和脑损伤严重程度升高导致存活率极低。
