液体负平衡在 ICU ＞60岁患者机械通气撤机过程中的应用

摘要

目的：探讨在保证循环稳定前体下液体负平衡对达撤机条件的＞60岁ICU患者撤机的影响。方法采用前瞻性随机对照研究，选择我科2013－02～2015－02收治的42例需要机械通气的＞60岁的危重症患者，在符合撤机标准后，随机分为液体负平衡组（ A组）和液体正平衡组（ B组），依中心静脉压（ CVP）、平均动脉压（ MAP）进行液体管理，至成功撤机48 h。比较两组患者一次撤机成功率、机械通气时间、血流动力学参数、液体平衡状况、BNP前体（ NT－pro－BNP）水平的变化。结果液体负平衡组患者撤机成功率（85．7％）高于液体正平衡组（66．7％），但差异无统计学意义（P＞0．05）；液体负平衡组机械通气时间（5．99±1．83）d vs （8．04±3．99）d，脱机48 h BNP前体（424．71±302．67）pg／mL vs （653．19±483．39）pg／mL，明显低于液体正平衡组（P＜0．05）；撤机后48 h两组MAP[（81．43±7．31）mm Hg vs （84．95±7．76）mm Hg]与CVP [（7．38±2．58）mm H2O vs （8．81±3．25）mm H2O]比较差异无统计学意义（P＞0．05）。结论在＞60岁危重症患者机械通气撤机过程中，在保证循环稳定前体下，采用适度液体负平衡策略有助于缩短机械通气时间、撤机成功，其机制可能与改善患者心功能有关。%Obj ective To investigate whether limited fluid management improves weaning outcomes compared with different fluid management on ICU elderly patients.Methods The design was a prospective, randomized, parallel group study in our Emergency Intensive Medicine Department. Forty-two patients who were up to weaning conditions were included from Feb 2013 to Feb 2015.The patients were divided into treatment group negative fluid balance( A group) and control group ( B group) according to random number table, with 21 cases in each group.A group received negative liquid balance 2 days before weaning and B group received positive fluid balance.Baseline indexes of two groups were compared, including respiration rate ( RR), heart rate, mean arterial pressure ( MAP), central venous pressure ( CVP) , blood gas, APACHEⅡ score, N-terminal -pro-brain natriuretic peptide (NT -pro -BNP).After ventilator weaning, liquid balance during weaning, failures of weaning, total length of mechanical ventilation were compared .Rseu lts Patients who received negative fluid balance had shorter mechanical ventilation time, lower NT -pro -BNP level. There were significant differences in total length of mechanical ventilation [(5.99 ±1.83)d vs (8.04 ±3.99) d], NT-pro-BNP [(424.71 ±302.67)pg/mL vs (653.19 ±483.39) pg/mL] between two groups (P<0.05).The success of weaning in A group was lower, but there was no statistically significant difference between the tow groups (85.7% vs 66.7%).There was no statistically significant difference in the heart rate, RR, MAP, CVP at the end of the investigation between the two groups ( P >0.05 ) . Conclusion Our results suggest that negative fluid balance strategies may be helpful in patients weaning from the mechanical ventilation.Its mechanism may be related to improvement of cardiac function in these elderly patients.