摘要
Abstract
Objective To investigate the relations between dynamic changes in blood gas analysis and prognosis of patients with acute respiratory failure ( ARF ) in chronic obstructive pulmonary disease ( COPD ) requiring invasive mechanical ventilation ( IMV ) . Methods A total of 83 hospitalized patients with acute exacerbated COPD requiring IMV in respiratory intensive care unit ( RTCU ) of our hospital hetween May 2008 and December 2009 were retrospectively analyzed. The changes of their daily arterial PaCO2, pH, and HCO3- were compared between the survival group ( n = 52 ) and the non - survival group ( n = 31 ). Multi - level linear model with time of stay at RICU ( days ) and group as fixed effects and patient number as random effect was used to analyze the blood gas changes with hospital stay and its relations with prognosis. Results Significant differences were observed between the survival group and the non - survival group in average pH value ( 7. 45 ± 0. 09 ) vs. ( 7. 39 ± 0. 11 ), HCO3-concentration ( 25. 3 ±4. 4 ) mmol/L vs. ( 22. 8 ±7. 2 ) mmol/L, and PaCO2 ( 37. 5 ±9. 8 ) mm Hg vs. ( 43. 2 ± 16. 3 ) mm Hg ( P <0. 05 ). The pH values of the two groups were significantly different on each day except day 8 ( P <0. 05 ). Between day 1 and day 5 , the pH value increased in both groups. During the last 3 days, pH value of the survival group stably set above 7. 45 , while the pH value of the non - survival group decreased and dropped to 7. 30 before death. Between day 4 and day 8 , no significant difference was observed between the two groups in HCO3- concentration ( P >0. 05 ). HCO3- concentration in the survival group was basically stable and remained between 24 - 26 mmol/L for 8 days, while that of the non - survival group increased gradually from below the reference value on day 1 to above the reference value on day 9. Except for day 1 and day 9 , no significant difference was observed in PaCO2 between the two groups ( P >0. 05 ). PaCO2 of the survival group greatly decreased after intubation and stayed at 35 - 36 mm Hg after tube removal; while PaCO2 of the non - survival group increased between day 6 and day 9 after intubation, and reached the highest level on day 9 ( even higher than day 1 ). Conclusion Patients in the survival group can maintain acid - base equilibrium after ventilation, while patients in the non - survival group show apparent acidosis during the last few days. pH value changes occur on several days during the RICU stay, while PaCO2 and HCO3- concentration change is apparent on the day of death.关键词
肺疾病,慢性阻塞性/呼吸重症监护室/机械通气/动脉血气分析/酸碱平衡Key words
Pulmonary disease, chronic obstructive/ Respiratory intensive care unit/ Mechanical ventilation/ Arterial blood gas analysis/ Acid - base balance分类
医药卫生
