低温复苏对猪心搏骤停后肺酶学和形态学的影响

The influence of hypothermia therapy on enzymology and pathology of lung after cardiac arrest

目的探讨低温对心搏骤停复苏成功后血清炎症因子、肺组织酶学及形态学的影响。方法对10只猪诱导心室纤颤（室颤）4min后给予标准心肺复苏，待自主循环恢复（ROSC）后按随机数字表法均分为两组。低温组立即给予4℃的生理盐水以1．33ml·kg^-1·min^-1补液22min，继之以10ml·kg^-1·h^-1补液4h；常温组采用室温生理盐水按相同用量和速度输入。实时监测血流动力学指标；分别于室颤前、ROSC后10min、2h、4h检测血清肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）含量；于ROSC后24h取肺组织检测ATP酶活性，同时行普通病理和超微结构观察。结果与常温组比较，低温组除可降低体温外，余血流动力学指标均无明显差异。低温组ROSC后10min、2h、4h血清TNF—α[（15．55±1．65）、（17．06±0．86）、（12．52±1．82）ng／L]和IL-6[（173．80±15．01）、（184．09±13．44）、（73．17±6．95）ng／L]均较常温组[TNF-α：（20．09±1．32）、（26．18±1．16）、（29．18±1．20）ng／L，IL-6：（176．92±16．68）、（239．17±13．18）、（405．48±55．49）ng／L3显著降低（P〈0．05或P〈0．01）。低温组较常温组能显著降低细胞膜Na＋-K＋-ATP酶活性[（3．78±1．14）U／L比（6．22±1．23）U／L，P〈0．013。低温组肺组织病理变化较常温组损伤轻。结论4℃生理盐水诱导的低温疗法能减少猪心搏骤停模型中炎症介质的释放，抑制肺泡细胞膜ATP酶的活性，并对肺组织形态学有一定的保护作用。

Objective To study the effect of hypothermia on pro-inflammatory mediators in serum, the enzymology and pathology of lung tissue. Methods Ventricular fibrillation for 4 minutes was induced in 10 domestic pigs. Standard cardiopulmonary resuscitation was given to them. They were then divided into two groups according to the random table after restoration of spontaneous circulation （ROSC）.. low temperature group （n：5）： pigs were given an infusion 30 ml/kg of 4 ℃ normal saline （NS） at an infusion rate of 1.33 ml ·kg^-1·min^-11, started after ROSC for 22 minutes, then 10 ml ·kg^-1 o h 1 for 4 hours; ambient temperature group （n± 5） received the same infusion of NS in room temperature. Hemodynamic parameters were observed, blood samples were collected to measure tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in serum before ventricular fibrillation and 10 minutes, 2 hours, 4 hours after ROSC. Na＋-K＋-ATPase of lung tissue was determined 24 hours after ROSC, and the pathology and ultrastructure of the lung were studied. Results There was no significant difference in the hemodynamic parameters, except the temperature, between low temperature and ambient temperature groups. TNF-α contents at 10 minutes, 2 hours, 4 hours after ROSC in low temperature group were （15.55±1.65）, （17.06±0. 86）, （12.52± 1.82） ng/L, and the IL-6 contents were （173.80± 15.01）, （184.09± 13.44）, （73.17± 6. 95） ng/L, while the TNF-α contents at 10 minutes, 2 hours, 4 hours after ROSC in ambient temperature group were （20. 09±1±1.32）, （26. 185±1.16）, （29.18±1.20） ng/L, and the IL-6 contents were （176.92± 16.68）, （239.17 ± 13.18）, （405.48± 55.49） ng/L. The pro-inflammatory mediators in low temperature group were reduced significantly （P〈0. 05 or P〈0.01）. Low temperature could significantly reduce the activity of Na＋-K＋-ATPase （（3.78±1.14） U/L vs. （6.22±1.23） U/L, P〈0. 013. The pathology of lung was milder in low temperature group compared with that of ambient temperature group. Conclusion Hypothermia therapy with infusion of 4 ℃ NS can reduce the release of pro-inflammatory mediators, inhibit the ATPase activity of alveolar membrane, and shows a protective effect on lung tissue against low perfusion.