Effect of perfluorocarbon partial liquid ventilation—induced hypothermia on dogs with acute lung injury

BACKGROUND Acute lung injury (ALI) is the damage of alveolar epithelial cells and capillary endothelial cells caused by various direct and indirect injury factors, resulting in diffuse pulmonary interstitial and alveolar edema, resulting in acute hypoxic respiratory insufficiency. This study aimed to investigate the effects of hypothermia induced by partial fluid ventilation on dogs with ALI. METHODS The experimental dogs were randomly divided into a conventional mechanical ventilation group (CMV) group, a normal temperature perfluorocarbon liquid ventilation group (NPLV) group, and a hypothermic perfluorocarbon liquid ventilation group (HPLV) group. After induction of ALI, the dogs of the CMV group was treated with CMV for respiratory support, the HPLV group was given a 15 °C low-temperature perfluorocarbon partial liquid ventilation (PLV), and the NPLV group was given partial fluid permeation of perfluorocarbon (PFC) at a room temperature of 37 °C. Anesthesia was stable at 0.5 h (T0), and successful modeling (T1), at 1 h (T2), 2 h (T3), 3 h (T4) and 4 h (T5) was completed. Blood gas analysis was performed, and rectum temperature, peak airway pressure (PIP), and lung compliance were measured. We performed enzyme-linked immunosorbent assay (ELISA) for peripheral blood and postoperative bronchoalveolar lavage fluid (BALF), calculation of lung tissue wet weight/dry weight ratio, and Western blot detection of NF-κB p65. RESULTS In the HPLV group, the blood gas index of dogs with ALI was close to normal. In T2¬-T5, the rectal temperature of the HPLV group was significantly lower than that of the NPLV group and the CMV group the lung compliance in the HPLV group and the NPLV group was lower than that in the CMV group at the T2-T5 time point, while the CLst value was significantly increased. The detection of peripheral blood and BALF in dogs showed that interleukin-10 (IL-10) was significantly increased and TNF-α was significantly decreased in the HPLV group compared with the CMV group and NPLV group. Compared with CMV group, the wet/dry ratio of lung tissue in the BALF of HPLV group was decreased. CONCLUSIONS The results indicate that mild hypothermia caused by partial fluid ventilation can increase oxygenation capacity, oxygen partial pressure, the expression of anti-inflammatory factor IL-10 and improve lung compliance in dogs with ALI.