[The study of continuous blood purification in severe asthma].

Objective: To explore the mechanism that continuous blood purification (CBP) improve the lung mechanical ventilation parameters, cytokine levels and blood gas analysis results in severe asthma patients, and compare the differences in those parameters between bicarbonate and lactate displacement liquid.

Methods: According to the random number table, 26 severe asthma patients were allocated into control group (n=10), bicarbonate group (n=8) and lactate group (n=8). Twenty-four hours treatment with mechanical ventilation (control group), mechanical ventilation + CBP (bicarbonate group) or mechanical ventilation + CBP (lactate group) were conducted respectively. Lung mechanical ventilation parameters, serum cytokine level and blood gas analysis results, arterial blood lactate, and electrolytes level were compared among groups.

Results: After 24-hour CBP, the lung mechanical ventilation parameters were improved, cytokine levels were decreased, and pH value and partial pressure of oxygen were improved in bicarbonate group and lactate group. The two kinds of displacement liquid had no influence in arterial partial pressure of oxygen (PaO(2)), arterial blood lactate, and serum electrolytes level. The pH value in lactate group was higher than that in bicarbonate group (7.39±0.05 vs. 7.30±0.01, P<0.01). The arterial partial pressure of carbon dioxide (PaCO(2)) was lower in lactate group than that in bicarbonate group (57.14±5.04 mm Hg vs. 89.00±3.66 mm Hg, P<0.01).

Conclusions: Combine CBP might improve the lung mechanical ventilation parameter, cytokine level and blood gas analysis more quickly in severe asthma treatment. The lactate displacement liquid improves the retention of carbon dioxide more.