负平衡超滤联合改良超滤对瓣膜置换患者术后肺功能和早期认知功能的影响

Effect of subzero-balanced ultrafiltration plus modified ultrafiltration on pulmonary function and early cognitive function in patients after cardiac valve replacement operation

目的观察负平衡超滤联合改良超滤对瓣膜置换患者术后肺功能和早期认知功能的影响。方法 60例择期行二尖瓣置换术的患者分为常规超滤组(CUF组)和负平衡超滤+改良超滤组(S+M组),每组各30例。CUF组于复温后开始超滤,转流结束前停止超滤;S+M组转流开始10 min后行负平衡超滤,停机后行改良超滤。于转流前(T1)、转流结束即刻(T2)、术后2(T3)、12(T4)和24 h(T5)取动脉血标本,做血气分析并测定肿瘤坏死因子-α(TNF-α)及白细胞介素-6(IL-6)的浓度;记录T1~T5各时间气道峰压(Peak)、呼吸停顿压(Ppause)、潮气量(TV)和吸入氧浓度(Fi O),计算肺静态顺应性(CLst)2、肺泡-动脉氧分压梯度(Aa DO2)及氧合指数(OI)。记录两组患者术中超滤量、清醒时间、呼吸机辅助呼吸时间。于麻醉前24 h、术后24、48和72 h时用简易精神状态量表(MMSE)测试患者的认知功能,记录术后72 h内术后认知功能障碍(POCD)的发生率。于转流前、超滤前及超滤后取动脉血,测定各时点患者血浆胶体渗透压(COP)及红细胞压积(Hct)。结果与T1相比,在T2~T5时两组患者CLst和OI均降低,Aa DO2、血浆内TNF-α及IL-6的浓度均升高;与CUF比较,在T2~T5时S+M组患者CLst和OI升高,Aa DO2、血浆内TNF-α及IL-6的浓度均降低,差异有统计学意义(P<0.05);与CUF组比较,S+M组患者超滤量明显增多,术后患者的清醒时间、呼吸机辅助时间均减少,差异有统计学意义(P<0.05);与术前24 h比较,两组患者术后24、48和72 h时的MMSE评分值均降低;与CUF组比较,S+M组患者术后48和72 h时MMSE评分值增加,术后72 h内POCD的发生率明显降低,差异有统计学意义(P<0.05)。超滤后S+M组患者血浆COP和Hct与CUF组相比均明显升高;两组患者超滤前后血浆COP、Hct比较均明显升高,差异有统计学意义(P<0.05)。结论术中使用负平衡超滤联合改良超滤可改善瓣膜置换患者术后肺功能和早期认知功能,有利于患者术后恢复。

[Objective] To observe the effect of subzero-balanced uhrafiltration and modified uhrafiltration on pulmonary function and early cognitive function in patients after heart valve replacement operation. [Methods] Sixty patients undergoing mitral valve replacement were randomly divided into conventional ultrafihration group （CUF） and subzero-balanced ultrafiltration plus modified ultrafihration group （S ＋ M） with thirty cases in each group. In the CUF group ultrafiltration was started after rewarming, and stopped before the end of cardiopulmonary bypass （CPB）. In the S ＋ M group subzero-balanced uhrafihration was started after CPB for 10 rain, modified ultra：filtration was started after stopping CPB. Arterial blood samples were extracted before CPB （T,） and instantly after CPB （T2）, at 2 （T3）, 12 （T4） and 24 h （Ts） after operation. Then blood gas analysis was done and the concentrations of tumor necrosis factor alpha （TNF-ot） and intedeukin-6 （IL-6） were detected. Peak airway pressure （Pm~,）, respiratory pause pressure （P~）, tidal volume （TV） and oxygen concentration （FiO2） were recorded at TI^Ts, and static lung compliance （CLst）, alveolar arterial oxygen partial pressure gradient （AaDO2） and oxygenation index （OI） were calculated. Intraoperative uhrafiltration volume, awakening time and mechanical ventilation time were recorded. The cognitive function of the patients was tested with the Mini Mental State Examination （MMSE） 24 h before anesthesia, and 24, 48 and ＂/2 h after surgery. The incidence of postoperative cognitive dysfunction （POCD） was recorded within 72 h after operation. Plasma colloid osmotic pressure and hematocrit of the patients were measured before CPB, before and after uhrafihration. [Results] In both groups, CLst and OI of the patients were lower, and AaDO2 and the concentrations of TNF-ot and IL-6 in plasma were higher at T2~T5 than those at Tl. At T2~Ts, CLst and OI were higher, and AaDO2 and the concentrations of TNF-ct and IL-6 were lower in the S ＋ M group than those in the CUF group, there were statistically significant differences （P 〈 0.05）. Uhrafihration volume increased, the postoperative awake time and mechanical ventilation time shortened in the S ＋ M group compared to those in the CUF group （P 〈 0.05）. The MMSE scores of the two groups 24, 48 and 72 h after operation were lower than those at 24 h before operation. The MMSE scores 48 and 72 h after operation in the S ＋ M group were more than those in the CUF group （P〈 0.05）. The incidence of POCD within 72 h after surgery in the S ＋ M group was lower than that in the CUF group （P 〈 0.05）. Plasma COP and Hct of the patients in the S ＋ M group were significantly higher than those in the CUF group after uhrafiltration. Plasma COP and Hct of the two groups significantly increased after uhrafihration compared with those before ultrafihration （P 〈 0.05）. [Conclusion] Subzero-balanced ultrafihration plus modified uhrafiltration can well improve postoperative pulmonary function and cognitive function of the patients accepting cardiac valve replacement.