亚低温治疗对急性呼吸窘迫综合征犬肺功能的影响

Efficacy of mild hypothermia therapy on pulmonary function in ARDS dogs

目的探讨亚低温治疗对急性呼吸窘迫综合征(ARDS)犬呼吸功能的影响。方法 25只健康杂种犬随机分为常温感染组(12只)和亚低温感染组(13只)。2组均通过股静脉泵入活大肠埃希菌制成高动力型感染性休克模型。常温感染组在常温下继续观察,亚低温感染组通过血管内降温实施亚低温治疗(33℃±1℃)。2组0、24、48 h通过PICCO采集肺血流动力学参数,呼吸机监测呼吸力学参数。72 h后处死动物,拍摄胸片及留取肺组织病理切片,判断是否发生ARDS。结果观察至72 h时,亚低温感染组及常温感染组分别有4只及7只发生ARDS。2组氧合指数(OI)、氧分压[p(O_2)]及肺静态顺应性(Cst)均随观察时间的延长逐渐降低,血管外肺水指数(EVLWI)、肺血管通透性指数(PVPI)、气道平台压(Pplat)及气道阻力(Raw)则随之逐渐升高(均P<0.05)。亚低温感染组上述指标均明显优于常温感染组。结论亚低温治疗可以改善感染性休克犬的肺功能和肺血流动力学状态,降低ARDS的严重程度。

Objective To investigate the efficacy of mild hypothermia therapy on pulmonary function in acute respiratory distress syndrome （ARDS） dogs. Methods A total of 25 healthy dogs were included and randomly divided into two groups, mild hypothermia treatment group （experimental group, n=12） and normothermia treatment group （control group, n=13）. The E. coli was pumped continuously into the canine femoral vein by micro pump to construct the septic shock model in two groups. The hypothermia experimental group was treated with hypothermia （33 ℃±1 ℃）, and the control group was observed at room temperature. The pulmonary hemodynamic parameters and respiratory mechanics parameters were supervised by PICCO and respirator respectively at 0, 24 and 48 h during the ARDS progress. Moreover, chest X-ray and lung tissue biopsy were taken to confirm the diagnosis of ARDS after 72 h. Results Up to 72 h, ARDS was found in the experimental group （n=4） and the control group （n=7） respectively. The oxygenation index （OI）, partial pressure of oxygen [p（O2）] and pulmonary static compliance （Cst） decreased gradually with the extension of time in two groups. On the contrary, the external venous lung water index （EVLWI）, pulmonary vascular permeability index （PVPI） and airway resistance （Raw） increased gradually （P 〈 0.05）. However, all the parameters were significantly better in mild hypothermia group than those of the normothermia group. Conclusion Mild hypothermia therapy can improve the pulmonary function and reduce the severity of ARDS in septic shock dogs.