J. Xu1,2,3, P. Shen1,2,4, S. Xia1,2, S. Liu1,2, Z. Li3, M. Zhang1,2 1Department Of Emergency Medicine,Second Affiliated Hospital, Zhejiang University School Of Medicine,Hangzhou, ZHEJIANG, China 2Institute Of Emergency Medicine,Zhejiang University,Hangzhou, ZHEJIANG, China 3Department Of Emergency Medicine,Yuyao People’s Hospital, Medical School Of Ningbo University,Yuyao, ZHEJIANG, China 4Department Of Intensive Care Medicine,The First Hospital Of Jiaxing,Jiaxing, ZHEJIANG, China
Introduction: Early investigations demonstrated that aortic balloon occlusion (ABO) improved cardiac and cerebral perfusion during resuscitation and the success of resuscitation in non-traumatic cardiac arrest. Recent investigations demonstrated that ABO was effective in controlling traumatic hemorrhage, however, a prolonged occlusion could result in irreversible organ injury. Here we investigated the effects of different durations of ABO on outcomes of traumatic cardiac arrest. We hypothesized that ABO would improve resuscitation success, and a 30-min ABO would be better to produce post-resuscitation organ protection compared with 60-min ABO in a pig model of traumatic cardiac arrest.
Methods: In 27 male pigs weighing 33 ± 4 kg, 45% of estimated blood volume was removed within 20 mins. The animals were then subjected to 5 mins of untreated ventricular fibrillation and 5 mins of cardiopulmonary resuscitation (CPR). Coincident with the start of CPR, the animals were randomized to receive either 30-min ABO (n=7), 60-min ABO (n=8) or control (n=12). Meanwhile, fluid resuscitation was initiated by the infusion of normal saline with 1.5 times of hemorrhage volume in one hour, and finished by the reinfusion of 50% of the shed blood in another one hour. The resuscitated animals were observed for 24 hrs. Continuous and categorical variables were compared with one way analysis of variance and Fisher’s exact test, respectively.
Results:During CPR, coronary perfusion pressure was significantly greater in the 30-min and 60-min ABO groups than the control group (36.7±2.2 and 36.6±2.9 vs. 27.7±3.0 mmHg, both P<0.005). The success rate of resuscitation was higher in animals received ABO compared to the control group (7/7 and 8/8 vs. 9/12, P= 0.26 and 0.24). After resuscitation, ejection fraction was significantly increased and cardiac troponin I was significantly decreased in the 30-min ABO group than the 60-min ABO and control groups (6-hr ejection fraction, 66±4 vs. 58±6 and 59±5 %, both P<0.05; 6-hr cardiac troponin I, 343±34 vs. 421±73 and 433±46 pg/ml, both P<0.05). Neurologic dysfunction and cerebral injury were also significantly alleviated in the 30-min ABO group compared to the other two groups (24-hr neurological deficit score, 124±20 vs. 173±31 and 190±31, both P<0.005; 24-hr neuron specific enolase, 20.2±3.3 vs. 27.1±2.7 and 28.5±1.1 ng/ml, both P<0.005). Additionally, serum creatinine, blood urea nitrogen, intestinal fatty acid binding protein and diamine oxidase were lower in the 30-min ABO group than the other two groups although statistically insignificantly different.
Conclusion:In a pig model of traumatic cardiac arrest, ABO augmented the efficacy of resuscitation. A 30-min ABO was superior to 60-min ABO in improving post-resuscitation cardiac and neurologic outcomes without exacerbating the injuries of kidney and intestine.