何忠杰 郭建中 黄庆 曹慧婕 赵宇 谢平初 翁志华 林洪远 100037 北京，解放军第304医院外科ICU(何忠杰、郭建中、黄庆、赵宇、谢平初、翁志华、林洪远)；总装备部司令部门诊部(曹慧婕) 中华内科杂志 1998 0 0 12


    关键词：心肺复苏术；血液动力学；氧 期刊 zhnkzz 0 论 著 fur -->


    

【摘要 】 目的 探讨胸外按压对全身血流动力学和氧代谢的影响。方法 13例使用机械通气和血流动力学监测的外科重症监护病房病人，在呼吸心跳停止后继续维持高浓度氧的机械通气，同时进行持续胸外按压(频率80～150次/分)。在此期间，每隔5分钟测量血流动力学指标和动、静脉血气，并计算氧代谢的各项指标。结果 (1)心排量在按压开始的1～3分钟内呈先升后降的变化，按压频率在100～150次/分内可获得较高的心排量。(2)所测各处压力不等，心脏灌注压为(42±51)/(6±14)mmHg(平均为15±25mmHg)。(3)肺循环阻力大于外周循环阻力，与生理情况相反；右心室功及右室每搏功下降幅度小于左心室功与左室每搏功。(4)氧载为生理的1/4，氧耗为生理的1/2,氧提取率为生理的2～3倍。结论 胸外按压在高频率时可能存在频率共振机制,最佳的共振频率可能在120～140次/分；氧耗与氧载仍存在依赖关系；心肺复苏过程中血流动力学和氧代谢呈不均一性。

Oxygen metabolism and hemodynamicduring cardiopulmonary resuscitation in human body He Zhongjie, Guo Jianzhong, Huang Qing, et al. Intensive CareUnit, The 304th Hospital of PLA, Beijing 100037

【Abstract 】 Objective To evaluate thehemodynamics and oxygen metabolism during cardiopulmonary resuscitation in human body.Methods Swan-Ganz catheter was introduced in 13critically ill patients, who were supported by ventilator and treated with closed chestcardiac massage (frequency 80～150/min) for 30minutes. Cardiac output (CO) and arterial and mixed venous blood gas analysis weremeasured every 5 minutes after cardiac arrest. Results (1) CO increased in the begining and decreased gradually in 1～3 minutes. Higher CO could be obtained with increased compressionfrequency (100～150/min). (2) Right atrial pressure(RAP), pulmonary arterial pressure (PAP), arterial pressure (AP) and AP-RAP (coronaryperfusion pressure) varied with the difference between the systolic and diastolicpressure. Coronary perfusion occurred mainly in the phase of pressing, but not relaxing.(3) Higher compression frequency led to better cardiac output because of the improvedfrequency resonance effect of the chest wall, thoracic cavity, cardiac chambers and large vesseles. (4) Pulmonary vascular resistance (PVR) was higher than systemic vascularresistance (SVR) and the decrement of right ventricular work (RVW) and right ventricularstroke work (RVSW) was less than that of left ventricular work (LVW) and left ventricularstroke work (LVSW). It means that the effect of compression exerts mainly on the pulmonarycirculation and right cardiac chambers. (5) Oxygen metabolism study showed that oxygendelivery (O₂ ) was almost 1/4 of the normal volume, oxygenconsumption (O₂ )half of the normal, and oxygen extraction ratio 2～3times of the normal range. O₂ was dependent on O₂ . (6) Alveolo-arteriolaroxygen tension difference and arterio-venous shunt fraction were abnormal. In 3 patientswith PaO₂ >60 and PaCO₂ <50 mmHg, life could be sustained.Conclusion (1) There might be a frequency resonancemachanism during high frequency compression. The best frequency was 120～140 beat/min. (2) O₂ in this study was less than the critical limitationand O₂ is dependent on O₂ .(3) CO, blood distribution and oxygen metabolism data were not stable in time sequentialanalysis, though the same effort was provided.

     ......