Weihua Zhang1, Yanbo Zhang2, Donghai Liu1, Yaobin Zhu3, Chenhui Qiao1, Jiaxiang Wang1, Yulin Xu4, Yang Liu4, Bin Li4, Yao Yang4. 1. Department of Cardiovascular Surgery, First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan 450052, China. 2. Department of Pediatric Heart Center, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China. Email: yanbozhang@126.com. 3. Department of Pediatric Heart Center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China. Email: zhuyaobin@yeah.net. 4. Department of Pediatric Heart Center, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China.
Abstract
BACKGROUND: Large animal cardiopulmonary bypass (CPB) models are expensive, and prevent assessment of neurocognitive function, and difficulties with long-term recovery. The purpose of this study was to establish a novel rat model of cardiopulmonary bypass for deep hypothermic circulatory arrest without blood priming. METHODS: Twenty adult male Sprague-Dawley rats weighing 450-560 g were randomized to CPB with deep hypothermic circulatory arrest (DHCA) and control groups, with 10 rats each. The experimental protocols, including blood and crystalloid fluid administration, anesthesia, orotracheal intubation, ventilation, cannulation, and heparinization were identical in both groups. After inducing cardiac arrest, the circuit was turned off and rats were left in a DHCA state for 15 minutes. Rats were rewarmed to 34°C to 35°C over a period of 36 to 42 minutes using CPB-assisted rewarming, a heating blanket, and a heating lamp along with administration of 0.1 mEq of sodium bicarbonate and 0.14 mEq of calcium chloride. The remaining priming volume was reinfused and animals were weaned from CPB. RESULTS: All CPB with DHCA processes were successfully achieved. Blood gas analysis and hemodynamic parameters were in the normal range. The vital signs of all rats were stable. CONCLUSIONS: Our CPB circuit has several novel features, including a small priming volume, active cooling/rewarming processes, vacuum-assisted venous drainage, peripheral cannulation without thoracotomy or sternotomy, and an accurate means of monitoring peripheral tissue oxygenation.
BACKGROUND: Large animal cardiopulmonary bypass (CPB) models are expensive, and prevent assessment of neurocognitive function, and difficulties with long-term recovery. The purpose of this study was to establish a novel rat model of cardiopulmonary bypass for deep hypothermic circulatory arrest without blood priming. METHODS: Twenty adult male Sprague-Dawley rats weighing 450-560 g were randomized to CPB with deep hypothermic circulatory arrest (DHCA) and control groups, with 10 rats each. The experimental protocols, including blood and crystalloid fluid administration, anesthesia, orotracheal intubation, ventilation, cannulation, and heparinization were identical in both groups. After inducing cardiac arrest, the circuit was turned off and rats were left in a DHCA state for 15 minutes. Rats were rewarmed to 34°C to 35°C over a period of 36 to 42 minutes using CPB-assisted rewarming, a heating blanket, and a heating lamp along with administration of 0.1 mEq of sodium bicarbonate and 0.14 mEq of calcium chloride. The remaining priming volume was reinfused and animals were weaned from CPB. RESULTS: All CPB with DHCA processes were successfully achieved. Blood gas analysis and hemodynamic parameters were in the normal range. The vital signs of all rats were stable. CONCLUSIONS: Our CPB circuit has several novel features, including a small priming volume, active cooling/rewarming processes, vacuum-assisted venous drainage, peripheral cannulation without thoracotomy or sternotomy, and an accurate means of monitoring peripheral tissue oxygenation.